Method of manufacturing capacitor element

ABSTRACT

There are provided a porous plate dielectric substance, pillar-shaped electrodes respectively formed in pores belonging to a first group and pores belonging to a second group alternately arranged on the dielectric substance, insulator layers made of an organic insulator formed on tips of pillar-shaped electrodes in the pores of the first and second groups so as to fill the pores and hide electrodes respectively provided on one principal surface and another principal surface of the dielectric substance and connected to base ends of the pillar-shaped electrodes.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a divisional application of U.S. patent application Ser. No.12/182,110, field Jul. 29, 2008, the disclosure of which is hereinincorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a capacitor element and a method ofmanufacturing the capacitor element in which a product of electrostaticcapacity and voltage proof (CV product) per unit volume is higher ascompared with electrolytic capacitors in related arts.

2. Background Art

An electrolytic capacitor using Al₂O₃ which is a kind of oxide of valvemetal as a dielectric film is widely used from the past. Theelectrolytic capacitor is formed by combination of a dielectric film andan electrolyte component, being polarized. The area is intended to beexpanded by roughening a surface of the Al₂O₃ film or some other ways,however, the attempt for higher capacity is reaching the limit. There isalso a problem that applications are limited because the capacitor ispolarized.

In order to solve the above problems and to allow the capacitor to havehigher capacity, the following proposal is made. Specifically, in PatentDocument 1, a method of obtaining a capacitor structure body isproposed, in which a porous substrate 4 having many pores 5 shown as aplan view in FIG. 35 is used as a mask, a first electrode 6 a is formedby regularly arranging many pillar-shaped bodies 2 a on a surface of asheet electrode 2 on a capacitor substrate 1 by a thin-film depositionprocess or etching as shown in FIG. 36 as a cross-sectional view, next,a dielectric thin film 8 is formed by depositing a dielectric materialhaving a permittivity of 100 or more on a surface of the first electrode6 a by using a MOCVD (organometallic vapor phase growing method), andfurther, a second electrode 6 b is formed on a surface of the dielectricthin film 8 as shown in FIG. 37 as a cross-sectional view.

-   [Patent Document 1] JP-A-2003-249417

However, in the manufacturing method of the capacitor structure body asdescribed in the above background art, the pillar-shaped bodies 2 a areformed by using the porous substrate 4 as a mask, therefore, adhesion ofthe electrode material in the porous substrate 4 and inner walls ofpores 5 of the porous substrate 4 and expansion of the pores 5 by theetching of the porous substrate 4 itself are liable to occur.Accordingly, there is a problem that it is difficult to obtain thepillar-shaped bodies 2 a having an uniform cross-sectional shape and adesired linear dimension.

In addition, the dielectric thin film 8 is formed by depositing thedielectric material having the permittivity of 100 or more on thesurface of the first electrode 6 a on which the pillar-shaped bodies 2 astand by using the MOCVD, therefore, when the height of thepillar-shaped bodies 2 a becomes high, the difference of film thicknessin the dielectric thin film 8 is liable to occur at a region facing asource gas and directly coming into contact with the source gas and at aregion not directly coming into contact with the source gas on thesurface of the first electrode 6 a. Therefore, there is a problem thatit is difficult to stably obtain a capacitor in which a product ofelectrostatic capacity and voltage proof (CV product) per unit volume ishigh.

SUMMARY OF THE INVENTION

The invention has been made in view of at least one of the aboveproblems, and in at least one embodiment, an object thereof is toprovide a capacitor element in which the CV product per unit volume ishigher as compared with electrolytic capacitors in related arts. In atleast one embodiment, another object thereof is to provide a capacitorelement which is not polarized.

Further in at least one embodiment, another object of thereof is toprovide a method of stably manufacturing a large-capacity capacitorelement which is not polarized.

In order to achieve one or more of the above objects, a capacitorelement according to an embodiment of the invention includes (1) aporous plate dielectric substance made of an oxide of a first valvemetal, in which plural pores belonging to a first group and poresbelonging to a second group, which pierce through in the thicknessdirection, are arranged alternately, first pillar-shaped electrodesformed in plural pores belonging to the first group respectively andbase ends thereof are exposed at one principal surface of the dielectricsubstance, and second pillar-shaped electrodes formed in plural poresbelonging to the second group respectively and base ends thereof areexposed at the other principal surface of the dielectric substance.Further, insulator layers are included, which are provided respectivelyon tips of the first pillar-shaped electrodes in the pores belonging tothe first group so as to fill the pores as well as on tips of the secondpillar-shaped electrodes in the pores belonging to the second group soas to fill the pores. Additionally, there are provided a first hideelectrode provided on one principal surface of the dielectric substanceso as to connect to base ends of the first pillar-shaped electrodes anda second hide electrode provided on the other principal surface of thedielectric substance so as to connect to base ends of the secondpillar-shaped electrodes.

Therefore, lowering of insulation performance of the capacitor can besuppressed even when voltage is applied and a CV product thereof isimproved as well as the capacitor is not polarized like an electrolyticcapacitor. Accordingly, voltage proof is improved, therefore, it ispossible to provide a capacitor element in which the CV product pervolume is higher than electrolytic capacitors of related arts as well asnot polarized.

According to a primary aspect of the capacitor element according to anembodiment of the invention, (2) in addition to the above (1), further,the insulator layer is formed by pyrolyzing electroconductive polymer.Accordingly, insulation performance can be obtained stably even atpositions in which filling of insulating resin is difficult such as theinside of pores belonging to the first group and the inside of poresbelonging to the second group.

According to an aspect of the capacitor element according to anembodiment of the invention, (3) in addition to the above second meansfor solving problems, further, voltage is applied between the first hideelectrode and the second hide electrode. According to this,short-circuit points between counter electrodes are burned off.Therefore, it is possible to provide a capacitor element in whichleakage current is reduced.

According to another primary aspect of a capacitor element of anembodiment of the invention, (4) in addition to the above first meansfor solving problems, further, the insulator layer is made of a TiO₂film. The TiO₂ film has higher permittivity as compared with an oxide(for example, Al₂O₃) of a first valve metal which forms a dielectriclayer. Accordingly, when the thickness of the insulating layer isallowed to be thin to a degree that is contributes to the capacity ofthe capacitor element, a capacitor element having higher capacity can beobtained.

According to another primary aspect of a capacitor element of anembodiment of the invention, (5) in addition to the above first meansfor solving problems, further, the insulator layer is made of an SiO₂film. Accordingly, a capacitor element having high insulationperformance can be provided.

According to another primary aspect of a capacitor element of anembodiment of the invention, (6) in addition to the above first meansfor solving problems, further, the insulator layer is made of aninsulating resin layer. Accordingly, a capacitor element having highinsulation performance can be provided.

According to another primary aspect of a capacitor element of anembodiment of the invention, (7) in addition to the above first meansfor solving problems, further, the insulator layer is made of an oxideof a second valve metal. Accordingly, a capacitor element having highinsulation performance can be provided.

According to another primary aspect of a capacitor element of anembodiment of the invention, (8) in addition to the above first meansfor solving problems, further, the insulator layer is made of air space.Accordingly, a capacitor element in which a resonance frequency infrequency impedance characteristics is high and high-frequencycharacteristics are excellent can be obtained.

A method of manufacturing a capacitor element according to an embodimentof the invention (9) includes a step of forming micro concave portionsat plural positions in a predetermined arrangement on one principalsurface of a foil of a first valve metal by indentation and a step offorming a porous plate dielectric substance by performing anodicoxidation to the foil of the valve metal and by forming concave portionsbelonging to a first group having a predetermined depth at positions inwhich the micro concave portions are formed and by forming concaveportions belonging to a second group having the depth shallower than theconcave portions belonging to the first group at positions betweenplural positions in which the micro concave portions are formed byanodic oxidation. The method further includes a step of forming a seedlayer at inner surfaces of the concave portions belonging to the firstgroup of the dielectric substance and at inner surfaces of the concaveportions belonging to the second group by electroless deposition byelectroless deposition as well as forming a first hide electrode on oneprincipal surface of the dielectric substance and a step of formingplural pores belonging to the first group opening at the other principalsurface side of the dielectric substance by removing bottom portions ofthe concave portions belonging to the first group of the dielectricsubstance by etching. The methods further includes a step of formingfirst pillar-shaped electrodes on the seed layer in the pores belongingto the first group by electrolytic plating, leaving tips of the pores ofthe other principal surface side of the dielectric substance and a stepof forming plural pores belonging the second group opening at the otherprincipal surface side of the dielectric substance by removing bottomportions of the concave portions belonging to the second group in thedielectric substance by etching. The methods further includes a step offorming electroconductive polymer layers on tips of the firstpillar-shaped electrodes in the pores belonging to the first group andon the first hide electrode in the pores belonging to the second groupso as to fill the pores respectively by electropolymerization and a stepof forming second pillar-shaped electrodes on the seed layer at innersurfaces of the pores belonging to the second group by electrolyticplating as well as forming a second hide electrode on the otherprincipal surface of the dielectric substance. The methods furtherincludes a step of forming an insulator layer by pyrolyizing theelectroconductive polymer layer to be insulated and a step of burningoff short-circuit points between the tips of the first pillar-shapedelectrodes and the second hide electrode and between the tips of thesecond pillar-shaped electrodes and the first electrodes by applyingvoltage.

Accordingly, it is possible to stably manufacture the capacitor elementhaving the structure in which the first pillar-shaped electrodes arehoused in the pores belonging to the first group of the porous platedielectric substance made of the oxide of the first valve metal and thesecond pillar-shaped electrodes are housed in the pores belonging to thesecond group respectively, as well as insulator layers are respectivelyprovided so as to fill the tips of the first pillar-shaped electrodes inthe pores belonging to the first group in which the insulationperformance is most liable to be reduced and so as to fill the tips ofthe second pillar-shaped electrodes in the pores belonging to the secondgroup. Therefore, the capacitor element having large capacity which isnot being polarized can be stably manufactured.

A method of manufacturing a capacitor element according to an embodimentof the invention (10) includes a step of forming micro concave portionsat plural positions in a predetermined arrangement on one principalsurface of a foil of a first valve metal by indentation and a step offorming a porous plate dielectric substance by performing anodicoxidation to the foil of the valve metal and by forming concave portionsbelonging to a first group having a predetermined depth at positions inwhich the micro concave portions are formed and by forming concaveportions belonging to a second group having the depth shallower than theconcave portions belonging to the first group at positions between theplural positions in which the micro concave portions are formed, a stepof forming plural pores belonging to the first group opening at theother principal surface side of the dielectric substance by removingbottom portions of concave portions belonging to the first group of thedielectric substance by etching, a step of forming a first feeding powerelectrode on one principal surface on which concave portions belongingto the second group of the dielectric substance are formed, a step offorming first pillar-shaped electrodes in the pores belonging to thefirst group by electrolytic playing, leaving tips of the pores of theother principal surface side of the dielectric substance, a step offorming an insulator layer on the tips of the first pillar-shapedelectrodes in the pores belonging to the first group so as to fill thepores respectively, a step of forming plural pores belonging to thesecond group opening at the other principal surface side of thedielectric substance by removing the first feeding power electrode onone principal surface of the dielectric substance and bottom portions ofthe concave portions belonging to the second group by etching, a step offorming a second hide electrode on the other principal surface of thedielectric substance, a step of forming second pillar-shaped electrodeson the second hide electrode in the pores belonging to the second groupby electrolytic plating, leaving the tips of the hole of one principalsurface side of the dielectric substance, a step of forming an insulatorlayer on tips of the second pillar-shaped electrodes in the poresbelonging to the second group so as to fill the pores respectively, anda step of forming a first hide electrode on one principal surface of thedielectric substance so as to touch base ends of the first pillar-shapedelectrodes. Accordingly, it is possible to stably manufacture thecapacitor element having the structure in which the first pillar-shapedelectrodes are housed in the pores belonging to the first group of theporous plate dielectric substance made of the oxide of the first valvemetal and the second pillar-shaped electrodes are housed in the poresbelonging to the second group respectively, as well as an insulatorlayer is provided between the tips of the first pillar-shaped electrodesand the second hide electrode so as to fill the pores belonging to thefirst group in which the insulation performance is most liable to bereduced and an insulator layer is provided between the tips of thesecond pillar-shaped electrodes and the first hide electrode so as tofill pores belonging to the second group.

According to another primary aspect of a method of manufacturing acapacitor element of an embodiment of the invention, (11) in addition tothe above tenth means for solving problems, further, in the step offorming the insulator layer on the tips of the first pillar-shapedelectrodes and the step of forming the insulator layer on the tips ofthe second pillar-shaped electrodes, electroconductive polymer films areformed by using the first feeding power electrode and the second feedingpower electrode as feeding power layers respectively, then, the filmsare insulated by pyrolysis. Accordingly, the capacitor element havinghigh insulation performance can be stably manufactured by the simplemanufacturing process.

According to another primary aspect of a method of manufacturing acapacitor element of an embodiment of the invention, (12) in addition tothe above tenth means for solving problems, further, in the step offorming the insulator layer on the tips of the first pillar-shapedelectrodes and the step of forming the insulator layer on the tips ofthe second pillar-shaped electrodes, TiO₂ electrodeposited films areformed by using the first feeding power electrode and the second hideelectrode as feeding power layers respectively, then, insulated byperforming heat treatment. Accordingly, the capacitor element can bestably manufactured by the simple manufacturing process.

According to another primary aspect of a method of manufacturing acapacitor element of an embodiment of the invention, (13) in addition tothe above tenth means for solving problems, further, in the step offorming the insulator layer on the tips of the first pillar-shapedelectrodes and the step of forming the insulator layer on the tips ofthe second pillar-shaped electrodes, SiO₂ films are formed byelectrolytic plating by using the first feeding power electrode and thesecond hide electrode as feeding power layers. Accordingly, thecapacitor element having high insulation performance can be stablemanufactured by the simple manufacturing process.

According to another primary aspect of a method of manufacturing acapacitor element of an embodiment of the invention, (14) in addition tothe above tenth means for solving problems, further, in the step offorming the insulator layer on the tips of the first pillar-shapedelectrodes and the step of forming the insulator layer on the tips ofthe second pillar-shaped electrodes, Sn—Pd plating layers are formed byusing the first feeding power electrode and the second hide electrode asfeeding power layers respectively, then, SiO₂ layers are wet-accumulatedon the Sn—Pd plating layers. Accordingly, the capacitor element havinghigh insulation performance can be stably manufactured by the relativelysimple manufacturing process.

A method of manufacturing a capacitor element according to an embodimentof the invention (15) includes a step of forming micro concave portionsat plural positions in a predetermined arrangement on one principalsurface of a foil of a first valve metal by indentation and a step offorming a porous plate dielectric substance by performing anodicoxidation to the foil of the valve metal and by forming concave portionsbelonging to a first group having a predetermined depth at positions inwhich the micro concave portions are formed and by forming concaveportions belonging to a second group having the depth shallower than theconcave portions belonging to the first group at positions between theplural positions in which the micro concave portions are formed, a stepof forming plural pores belonging to the first group opening at theother principal surface side of the dielectric substance by removingbottom portions of concave portions belonging to the first group of thedielectric substance by etching, a step of forming a first feeding powerelectrode on one principal surface on which concave portions belongingto the second group of the dielectric substance are formed, a step offorming first pillar-shaped electrodes on the feeding power electrode inpores belonging to the first group by electrolytic plating, leaving thetips of the pore of the other principal surface side of the dielectricsubstance, a step of forming plural pores belonging to the second groupopening at the other principal surface side of the dielectric substanceby removing the first feeding power electrode and bottom portions of theconcave portions belonging to the second group of the dielectricsubstance by etching, a step of forming an insulator layer on the tipsof the first pillar-shaped electrodes in the pores belonging to thefirst group and plural pores belonging to the second group so as to fillthe pores respectively, a step of forming a second hide electrode on theother principal surface of the dielectric substance, a step of formingsecond pillar-shaped electrodes on the second hide electrode in thepores belonging to the second group by electrolytic plating, leavingtips of the pores of one principal surface side of the dielectricsubstance, a step of forming an insulator layer on the tips of thesecond pillar-shaped electrodes in the pores belonging to the secondgroup so as to fill the pores respectively and a step of forming a firsthide electrode on one principal surface of the dielectric substance soas to touch base ends of the first pillar-shaped electrodes.Accordingly, it is possible to stably manufacture the capacitor elementhaving the structure in which the first pillar-shaped electrodes arehoused in the pores belonging to the first group of the porous platedielectric substance made of the oxide of the first valve metal and thesecond pillar-shaped electrodes are housed in the pores belonging to thesecond group respectively, as well as insulator layers are respectivelyprovided so as to fill the tips of the first pillar-shaped electrodes inthe pores belonging to the first group in which the insulationperformance is most liable to be reduced and so as to fill the tips ofthe second pillar-shaped electrodes in the pores belonging to the secondgroup.

According to another primary aspect of a method of manufacturing acapacitor element of an embodiment of the invention, (16) in addition tothe above fifteenth means for solving problems, further, in the step offorming the insulator layer on the tips of the first electrodes, aninsulating resin is buried on tips of the first pillar-shaped electrodesin the pores belonging to the first group and the pores belonging to thesecond group respectively, then, the insulating resin in the poresbelonging to the second group is removed. In the step of forming theinsulator layer on the tips of the second pillar-shaped electrodes, aninsulating resin is buried on tips of the second pillar-shapedelectrodes of the pores belonging to the second group. Accordingly, thecapacitor element having high insulation performance can be stablymanufactured by the relatively simple process.

According to another primary aspect of a method of manufacturing acapacitor element of an embodiment of the invention, (17) in addition tothe above fifteenth means for solving problems, further, in the step offorming the insulator layer on the tips of the first electrodes, aninsulating resin film is formed on the other principal surface of thetips side of the first pillar-shaped electrodes of the dielectricsubstance, then, the insulating resin film on the other principalsurface except the inside of pores belonging to the first group isremoved. In the step of forming the insulator layer on the tips of thesecond pillar-shaped electrodes, an insulating resin film is formed onone principal surface of tips side of the second pillar-shapedelectrodes of the dielectric substance, then, the insulating resin filmon one principal surface except the inside of the pores belonging to thesecond group is removed. Accordingly, the capacitor element having highinsulation performance can be stably manufactured by the relativelysimple process.

A method of manufacturing a capacitor element according to an embodimentof the invention (18) includes a step of forming micro concave portionsat plural positions in a predetermined arrangement on one principalsurface of a foil of a first valve metal by indentation and a step offorming a porous plate dielectric substance by performing anodicoxidation to the foil of the valve metal and by forming concave portionsbelonging to a first group having a predetermined depth at positions inwhich the micro concave portions are formed and by forming concaveportions belonging to a second group having the depth shallower than theconcave portions belonging to the first group at positions between theplural positions in which the micro concave portions are formed, a stepof forming plural pores belonging to the first group opening at theother principal surface side of the dielectric substance by removingbottom portions of concave portions belonging to the first group of thedielectric substance by etching, a step of forming a first feeding powerelectrode on one principal surface on which concave portions belongingto the second group of the dielectric substance are formed, a step offorming first pillar-shaped on the feeding power electrode in poresbelonging to the first group by electrolytic plating, leaving the tipsof the pore of the other principal surface side of the dielectricsubstance, a step of forming plural pores belonging to the second groupopening at the other principal surface of the dielectric substance byremoving bottom portions of concave portions belonging to the secondgroup of the dielectric substance by etching, a step of forming asecond-valve metal layer on the other principal surface of the tips sideof the first pillar-shaped electrodes of the dielectric substance, astep of removing the second-valve metal layer on the other principalsurface except the inside of pores belonging to the first group, a stepof forming an insulator layer on the tips of the first pillar-shapedelectrode in pores belonging to the first group as well as into pluralpores belonging to the second groups by performing anodic oxidation tothe second-valve metal layer using the first feeding power electrode asa feeding power layer so as to fill the pores respectively, a step ofremoving the first feeding power electrode by etching, a step of forminga second hide electrode on the other principal surface of the dielectricsubstance, a step of forming second pillar-shaped electrodes on thesecond hide electrode in the pores belonging the second group byelectrolytic plating, leaving tips of the pores of one principal surfaceside of the dielectric substance, a step of forming the second-valvemetal layer on one principal surface of the tips side of the secondpillar-shaped electrodes of the dielectric substance, a step of removingthe second-valve metal layer on one principal surface except the insideof pores belonging to the second group, a step of forming an insulatorlayer on the tips of the second pillar-shaped electrodes in the poresbelonging to the second group so as to fill the pores and a step offorming a first hide electrode on one principal surface of thedielectric substance so as to touch based ends of the firstpillar-shaped electrodes by performing anodic oxidation to thesecond-valve metal layer by using the second hide electrode as a feedingpower layer. Accordingly, it is possible to stably manufacture thecapacitor element having the structure in which the first pillar-shapedelectrodes are housed in the pores belonging to the first group of theporous plate dielectric substance made of the oxide of the first valvemetal and the second pillar-shaped electrodes are housed in the poresbelonging to the second group respectively, as well as insulator layersare respectively provided so as to fill the tips of the firstpillar-shaped electrodes in the pores belonging to the first group inwhich the insulation performance is most liable to be reduced and so asto fill the tips of the second pillar-shaped electrodes in the poresbelonging to the second group.

A method of manufacturing a capacitor element according to an embodimentof the invention (19) includes a step of forming micro concave portionsat plural positions in a predetermined arrangement on one principalsurface of a foil of a first valve metal by indentation and a step offorming a porous plate dielectric substance by performing anodicoxidation to the foil of the valve metal and by forming concave portionsbelonging to a first group having the predetermined depth at positionsin which the micro concave portions are formed and by forming concaveportions belonging to a second group having the depth shallower than theconcave portions belonging to the first group at positions between theplural positions in which the micro concave portions are formed, a stepof forming plural pores belonging to the first group opening at theother principal surface side of the dielectric substance by removingbottom portions of concave portions belonging to the first group of thedielectric substance by etching, a step of forming a first feeding powerelectrode on one principal surface on which concave portions belongingto the second group of the dielectric substance are formed, a step offorming first pillar-shaped electrodes on the feeding power electrode inpores belonging to the first group by electrolytic plating, leaving thetips of the pore of the other principal surface side of the dielectricsubstance, a step of forming plural pores belonging to the second groupopening at the other principal surface of the dielectric substance byremoving the first feeding power electrode and bottom portions ofconcave portions belonging to the second group of the dielectricsubstance by etching, a step of forming a second hide electrode on theother principal surface of the dielectric substance by sputteringthrough air space between the tips of the first pillar-shaped electrodesand the second hide electrode, a step of forming second pillar-shapedelectrodes on the second hide electrode in the pores belonging to thesecond group by electrolytic plating, leaving tips of the pores of oneprincipal surface side of the dielectric substance and a step of forminga first hide electrode connecting to base ends of the firstpillar-shaped electrodes on one principal surface of the dielectricsubstance by sputtering through air space between the tips of the secondpillar-shaped electrodes and the first hide electrode. Accordingly, itis possible to stably manufacture the capacitor element having thestructure in which the first pillar-shaped electrodes are housed in thepores belonging to the first group of the porous plate dielectricsubstance made of the oxide of the first valve metal and the secondpillar-shaped electrodes are housed in the pores belonging to the secondgroup respectively, as well as a step of forming insulator layers on thetips of the first pillar-shaped electrodes and tips of the secondpillar-shaped electrodes respectively can be omitted to manufacture thecapacitor element by the simple manufacturing process.

For purposes of summarizing aspects of the invention and the advantagesachieved over the related art, certain objects and advantages of theinvention are described in this disclosure. Of course, it is to beunderstood that not necessarily all such objects or advantages may beachieved in accordance with any particular embodiment of the invention.Thus, for example, those skilled in the art will recognize that theinvention may be embodied or carried out in a manner that achieves oroptimizes one advantage or group of advantages as taught herein withoutnecessarily achieving other objects or advantages as may be taught orsuggested herein.

Further aspects, features and advantages of this invention will becomeapparent from the detailed description which follows.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features of this invention will now be described withreference to the drawings of preferred embodiments which are intended toillustrate and not to limit the invention. The drawings areoversimplified for illustrative purposes and are not to scale.

FIG. 1 is a cross-sectional view showing an internal structure of acapacitor element according to a first embodiment of the invention;

FIG. 2 is a cross-sectional view showing a modification example of acapacitor element according to the first embodiment;

FIG. 3 is a flowchart showing the sequence of manufacturing processes ofan example of a first embodiment in a method of manufacturing thecapacitor element according to the disclosed embodiments;

FIG. 4A to FIG. 4E are views showing respective processes of the exampleof the first embodiment;

FIG. 5F to FIG. 5I are views showing respective processes of the exampleof the first embodiment;

FIG. 6J to FIG. 6M are views showing respective processes of the exampleof the first embodiment;

FIG. 7 is a flowchart showing the sequence of manufacturing processes ofanother example of the first embodiment;

FIG. 8 is a flowchart showing the sequence of manufacturing processes ofan embodiment of a second embodiment in a method of manufacturing thecapacitor element according to the disclosed embodiments;

FIG. 9G2 to FIG. 9I2 are views showing respective processes of thesecond embodiment;

FIGS. 10K21, 10K22, 10J22 and 10F22 are views showing respectiveprocesses of the second embodiment;

FIG. 11 is a flowchart showing the sequence of manufacturing processesof an example of the second embodiment;

FIGS. 12J211, 12J212, 12J221, and 12J222 are views showing formingprocesses of insulator layers of the example of the second embodiment;

FIG. 13 is a flowchart showing the sequence of manufacturing processesof an example of a third embodiment in a method of manufacturing thecapacitor element according to the disclosed embodiments;

FIGS. 14J311, 14J312, 14J321 and 14J322 are views showing formingprocesses of insulator layers of the example of the third embodiment;

FIG. 15 is a flowchart showing the sequence of manufacturing processesof an example of a fourth embodiment in a method of manufacturing thecapacitor element according to the disclosed embodiments;

FIG. 16 is a flowchart showing the sequence of manufacturing processesof an example of a fifth embodiment in a method of manufacturing thecapacitor element according to the disclosed embodiments;

FIGS. 17J511, 17J512, 17J521 and 17J522 are views showing formingprocesses of insulator layers of the example of the fifth embodiment;

FIG. 18 is a flowchart showing the sequence of manufacturing processesof an example of a sixth embodiment in a method of manufacturing thecapacitor element according to the disclosed embodiments;

FIGS. 19G6, 19F61, 19H6, 19I6 and 19J61 are views showing respectiveprocesses of an example of the sixth embodiment;

FIGS. 20K61, 20K62, 20J62 and 20F62 are views showing respectiveprocesses of an example of the sixth embodiment;

FIG. 21 is a flowchart showing the sequence of manufacturing processesof the example of the sixth embodiment;

FIG. 22J611 and FIG. 22J612 are views showing forming processes of aninsulator layer of the example of the sixth embodiment;

FIG. 23 is a flowchart showing the sequence of manufacturing processesof an example of a seventh embodiment in a method of manufacturing thecapacitor element according to the disclosed embodiments;

FIGS. 24K711, 24J712, 24J721 and 24J722 are views showing formingprocesses of insulator layers of the example of the seventh embodiment;

FIG. 25 is a flowchart showing the sequence of manufacturing processesof an example of an eighth embodiment in a method of manufacturing thecapacitor element according to the disclosed embodiments;

FIGS. 26G8, 26F81, 26H8, 26I81 and 26J811 are views showing respectiveprocesses of the example of the eight embodiment;

FIGS. 27J812, 27J813, 27I82, 27K81 and 27K82 are views showingrespective processes of the example of the eight embodiment;

FIGS. 28J821, 28J822, 28J823 and 28F82 are views showing respectiveprocesses of an example of the eight embodiment;

FIG. 29 is a flowchart showing the sequence of manufacturing processesof an example of a ninth embodiment in a method of manufacturing thecapacitor element according to the disclosed embodiments;

FIGS. 30G9, 30F91, 30H9 and 30I9 are views showing respective processesof the example of the ninth embodiment;

FIGS. 31K91, 31K92 and 31F92 are views showing respective processes ofthe example of the ninth embodiment;

FIG. 32 is a cross-sectional view showing an internal structure of afirst embodiment of a capacitor using the capacitor element according tothe disclosed embodiments;

FIG. 33 is a cross-sectional view showing an internal structure of asecond embodiment of a capacitor using the capacitor element accordingto the disclosed embodiments;

FIG. 34 is a cross-sectional view showing an internal structure of anembodiment of a capacitor-buried multilayer interconnection substrateusing the capacitor element according to the disclosed embodiments;

FIG. 35 is a view showing a method of manufacturing a capacitor elementof a background art;

FIG. 36 is a view showing a method of manufacturing the capacitorelement of the background art; and

FIG. 37 is a cross-sectional view showing an internal structure of thecapacitor element of the background art.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Next, a capacitor element according to a first embodiment of theinvention will be explained with reference to FIG. 1A, FIG. 1B and FIG.2C to FIG. 2E. FIG. 1A and FIG. 1B are expanded sectional views forexplaining an internal structure of a capacitor element 10 of the firstembodiment, in which FIG. 1A is a traverse cross-sectional view takenalong A-A line and FIG. 1B is a longitudinal cross-sectional view takenalong B-B line. FIG. 2C to FIG. 2E are transverse cross-sectional viewsshowing an internal structure of a modification example of the capacitorelement 10 of the first embodiment.

As shown in FIG. 1A and FIG. 1B, the capacitor element 10 of the firstembodiment includes a porous plate dielectric substance 14 made of anoxide of a first valve metal, pillar-shaped electrodes 16 a, 16 brespectively formed in pores 15 a 3 belonging to a first group and pores15 b 3 belonging to a second group, which are arranged alternately inthe dielectric substance 14, insulator layers 18 a, 18 b made of anorganic insulator layer formed on tips “t” of the pillar-shapedelectrodes 16 a in the pores 15 a 3 belonging to the first group and ontips “t” of the pillar-shaped electrodes 16 b in the pores 15 b 3belonging to the second group, and hide electrodes 12 a, 12 b providedon one and the other principal surfaces 14 a, 14 b of the dielectricsubstance 14 respectively and connected to the pillar-shaped electrodes16 a, 16 b respectively.

The pillar-shaped electrodes 16 a, 16 b include first pillar-shapedelectrodes 16 a formed in the pores 15 a 3 belonging to the first groupand second pillar-shaped electrodes 16 b formed in the pores 15 b 3belonging to the second group. As shown in FIG. 1A, the arrangement ofthe pores 15 a 3 belonging to the first group and the pores 15 b 3belonging to the second group has a structure in which, when a specificpore is taken as a center and the periphery thereof is divided equallyinto six, pores belonging to the same group are adjacent only in twodirections opposite to each other, sandwiching the specific pore, andpores belonging to the other group surround the specific pore in theother four directions. Further, in a longitudinal cross section takenalong B-B line shown in FIG. 1A, as shown in FIG. 1B, the pores 15 a 3belonging to the first group the pores 15 b 3 belonging to the secondgroup are arranged alternately in the traverse direction. In otherwords, the alternate arrangement is linearly repeated continuously inlines adjacent in the upper direction and in lines adjacent in the lowerdirection. In this case, since symmetric property for a magnet field isexcellent, a capacitor element is suitable for applications of ahigh-frequency circuit, in which equivalent series inductance (ESL) islow.

More specifically, the capacitor element 10 according to the embodimentincludes the porous plate dielectric substance 14 made of an oxide of afirst valve metal in which plural pores 15 a 3 belonging to the firstgroup and pores 15 b 3 belonging to the second group which piercethrough in the thickness direction alternately,

the first pillar-shaped electrodes 16 a formed in the plural pores 15 a3 belonging to the first group respectively, in which base ends “b”thereof are exposed at one principal surface of the dielectric substance14 and

the second pillar-shaped electrodes 16 b formed in the plural pores 15 b3 belonging the second group respectively, in which base ends “b”thereof are exposed at the other principal surface of the dielectricsubstance 14. Further, the capacitor element 10 includes the insulatorlayers 18 a, 18 b made of an organic insulator layer respectivelyprovided in the pores 15 a 3 belonging to the first group so as to fillthe tips “t” of the first pillar-shaped electrodes 16 a and in the pores15 b 3 belonging to the second group so as to fill tips “t” of thesecond pillar-shaped electrodes 16 b, the first hide electrode 12 aprovided on one principal surface 14 a of the dielectric substance 14and connected to the base ends “b” of the first pillar-shaped electrodes16 a and the second hide electrode 12 b provided on the other principalsurface 14 b of the dielectric substance 14 and connected to the baseends “b” of the second pillar-shaped electrodes 16 b.

The arrangement of the pores 15 a 3 belonging to the first group and thepores 15 b 3 belonging to the second group in the dielectric substance14 is not limited to the above, and it is also preferable to applyvarious modifications as shown, for example, in FIG. 2C to FIG. 2Ebelow.

A capacitor element 10′ whose traverse cross-section is shown in FIG. 2Chas the same longitudinal cross-section as the FIG. 1B in A′-A′ line, inwhich pores 15 a 3′ belonging to a first group and pores 15 b 3′belonging to a second group are alternately arranged in the transversedirection. The alternate arrangement is repeated in a herringbone shapecontinuously in lines adjacent in the upper direction and lines adjacentin the lower direction. In this case, orientation property of themagnetic field tends to be reduced to some degree and the ESL tends tobe increased to some degree as compared with the former capacitorelement 10.

A capacitor element 10″ whose transverse cross-section is shown in FIG.2D has the same longitudinal cross-section in A″-A″ line as the FIG. 1B,in which pores 15 a 3″ belonging to a first group and pores 15 b 3″belonging to a second group are alternately arranged in the transversedirection. The alternate arrangement is repeated in a herringbone shapein the upper direction and the lower direction on alternate lines. Inthis case, the number of the first pillar-shaped electrodes is differentfrom the number of the second pillar-shaped electrodes, therefore,electric current proof (ripple proof) property is reduced to some degreeas compared with the previous capacitor element 10. The ESL tends to beincreased as compared with the above.

Further, a capacitor element 10′″ whose transverse cross-section isshown in FIG. 2E has the same longitudinal cross-section in A′″-A′″ lineas the FIG. 1B, in which pores 15 a 3′″ belonging to a first group andpores 15 b 3′″ belonging to a second group are alternately arranged inthe transverse direction. The alternate arrangement is linearly repeatedin the upper direction and the lower direction on alternate lines. Inthis case, the number of the first pillar-shaped electrodes is differentfrom the number of the second pillar-shaped electrodes in the samemanner as the case of the capacitor element 10″, therefore, electriccurrent proof (ripple proof) property is reduced to some degree ascompared with the previous capacitor element 10. The ESL tends to beincreased as compared with the above.

In addition to the above configuration, the capacitor element 10according to the embodiment has the organic insulator layers in whichelectroconductive polymer layers 17 a, 17 b are thermally decomposed.

In addition to the above configuration, the capacitor element 10according to the embodiment further has a configuration in which voltageis applied between the first hide electrode 12 a and the second hideelectrode 12 b and short-circuit points between the tip “t” of the firstpillar-shaped electrode 16 a and the second hide electrode 12 b andshort-circuit points between the tip “t” of the second pillar-shapedelectrode 16 b and the first hide electrode 12 a are burned off.

Next, a method of manufacturing the capacitor element according to afirst embodiment of the invention will be explained with reference toFIG. 3 to FIG. 6. FIG. 3 is a flowchart showing an outline of an exampleof manufacturing process in the method of manufacturing the capacitorelement 10 of the embodiment. FIG. 4 to FIG. 6 are longitudinalcross-sectional views corresponding to FIG. 1B for explaining respectiveprocesses of the manufacturing process in the order of FIG. 4A to FIG.4E, FIG. 5F to FIG. 5I, and FIG. 6J to FIG. 6M. Note that signs put torespective processes in FIG. 3 correspond to signs in parentheses ofFIG. 4 to FIG. 6.

First, an outline of the method of manufacturing the capacitor elementaccording to the embodiment is as follows as shown in FIG. 3, a: a foilof a first valve metal is prepared, b, (d): micro concave portions areformed on one principal surface of the foil by, for example,indentation. Next, c, e: a dielectric substance including concaveportions belonging to a first group and concave portions belonging to asecond group having different depths on the one principal surface of thefoil is formed by, for example, anodic oxidation. Next, f: a seed-layeris formed at inner surfaces of the concave portions by, for example,electroless deposition. Next, g: bottom portions of the concave portionsbelonging to the first group are removed by, for example, a chemicaletching to form pores belonging to the first group. Next, h: firstpillar-shaped electrodes are formed in the pores belonging to the firstgroup, leaving tips of pores of the other principal surface side of thedielectric substance by, for example, electrolytic plating as well as afirst hide electrode is formed at one principal surface of the porousplate dielectric substance. Next, i: bottom portions of the concaveportions belonging to the second group are removed by, for example,chemical etching to form pores belonging to the second group. Next, j:electroconductive polymer layers are formed so as to fill the poresbelonging to the first group and the pores belonging to the second groupby, for example, electropolymerization. Next, k: second pillar-shapedelectrodes are formed in the pores belonging to the second group,leaving tips of pores of one principal surface side of the dielectricsubstance by, for example, electrolytic plating as well as a second hideelectrode is formed at the other principal surface of the porous platedielectric substance. Next, l: the electroconductive polymer layers areinsulated by, for example, pyrolysis. Next, m: short-circuit pointsbetween counter electrodes are burned off by, for example, applyingvoltage.

More specifically, first, as shown in FIG. 4A, a foil 13 made of a firstvalve metal such as Al is prepared.

Next, as shown in FIG. 4B, the foil 13 of the first valve metal isplaced on a support 11, and so-called indentation is performed, whichpresses a die 11 a in which micro bumps 11 a 1 are formed at pluralpositions on one principal surface in a predetermined arrangement on oneprincipal surface 13 a of the foil 13, thereby forming micro concaveportions 15 a 1 at plural positions on one principal surface 13 a of thefoil 13 in the predetermined arrangement.

Next, as shown in FIG. 4C, concave portions 15 a 2 belonging to thefirst group are formed at positions in which the micro concave portions15 a 1 are formed by performing anodic oxidation to the foil 13 of thefirst valve metal. If necessary, as shown in FIG. 4D, the so-calledindentation is performed, which presses a die 11 b in which micro bumps11 b 1 are formed at plural positions on one principal surface in apredetermined arrangement in the same manner as the above on oneprincipal surface 13 a of the foil 13 at positions between pluralpositions in which the micro concave portions 15 a 1 are formed, therebyforming micro concave portions 15 b 1 at plural positions on oneprincipal surface 13 a of the foil 13 in the predetermined arrangement.Further anodic oxidation is performed to the foil 13.

Accordingly, as shown in FIG. 4E, concave portions 15 a 2 belonging tothe first group having a predetermined depth are formed at positions inwhich the micro concave portions 15 a 1 are formed, and concave portions15 b 2 belonging to the second group having a depth shallower than theconcave portions 15 a 2 belonging to the first group are formed atpositions between plural positions in which the micro concave portions15 a 1 are formed respectively to thereby form the porous-platedielectric substance 14.

Next, as shown in FIG. 5F, a seed-layer S is formed at inner surfaces ofthe concave portions 15 a 2 belonging to the first group of thedielectric substance 14 as well as inner surfaces of the concaveportions 15 b 2 belonging to the second group by electroless deposition,and a first hide electrode 12 a is formed on one principal surface 14 aof the dielectric substance 14.

Next, as shown in FIG. 5G, bottom portions of the concave portions 15 a2 belonging to the first group of the dielectric substance 14 areremoved by chemical etching to form plural pores 15 a 3 belonging to thefirst group opening in the other principal surface 14 b side of thedielectric substance 14.

Next, as shown in FIG. 5H, first pillar-shaped electrodes 16 a whosebase ends “b” are connected to the first hide electrode 12 a are formed,by electrolytic plating, on the seed-layer S in pores 15 a 3 belongingto the first group of the dielectric substance 14, leaving tips of thepores 15 a 3 of the other principal surface 14 b side of the dielectricsubstance 14. At this time, it is preferable that tips “t” of thepillar-shaped electrodes 16 a have the length not reaching the otherprincipal surface 14 b of the dielectric substance 14.

Next, as shown in FIG. 5I, bottom portions of the concave portions 15 b2 belonging to the second group of the dielectric substance 14 areremoved by chemical etching to form plural pores 15 b 3 belonging to thesecond group opening at the other principal surface 14 b side of thedielectric substance 14.

Next, as shown in FIG. 6J, electroconductive polymer layers 17 a, 17 bare formed on the tips “t” of the first pillar-shaped electrodes 16 a inthe pores 15 a 3 belonging to the first group of the dielectricsubstance 14 as well as on the first hide electrode 12 a in the pores 15b 3 belonging to the second group so as to fill the pores 15 a 3, 15 b 3respectively by electropolymerization.

Next, as shown in FIG. 6K, the second electrodes 16 b are formed on theseed-layer S at inner surfaces of the pores 15 b 3 belonging to thesecond group of the dielectric substance 14 as the electrolytic platingas well as a second hide electrode 12 b is formed on the other principalsurface 14 b of the dielectric substance 14.

Next, as shown in FIG. 6L, the electroconductive polymer layers 17 a, 17b are pyrolyzed and insulated by heating the dielectric substance 14obtained as the above at 300° C. to form insulator layers 18 a, 18 bmade of an organic insulator layer. The whole resistance value ofleakage current of the electroconductive polymer layers 17 a, 17 bbefore the above pyrolysis is, for example, 0.8 mΩ. The whole resistancevalue of leakage current of the insulator layers 18 a, 18 b made of theorganic insulator layer after the pyrolysis is, for example, 50 kΩ

Next, short-circuit points between the tips “t” of the firstpillar-shaped electrodes 16 a and the second hide electrode 12 b andbetween the tips “t” of the second pillar-shaped electrodes 16 b and thefirst hide electrode 12 a are burned off by applying voltage to obtainthe capacitor element 10 according to the embodiment as shown in FIG.6M.

Next, a preferred embodiment of the foil 13 of the first valve metal isas follows. Specifically, it is preferable to apply Al as the firstvalve metal, however, it is not limited to this, and it is alsopreferable to apply elemental substances of Ta, Nb, Ti, Hf, W and V oralloys thereof. As the foil 13 of the first valve metal, it ispreferable that one capacitor element is formed from a sheet of foil orthat plural capacitor elements are formed from a sheet of foil. When onecapacitor element is formed from a sheet of foil, it is preferable, forexample, to apply the length 10 mm×the width 10 mm to the length 1mm×the width 1 mm and the thickness of 20 μm to 500 μm. When pluralcapacitor elements are formed from a sheet of foil, it is preferable,for example, to apply the length 500 mm×the width 500 mm to the length10 mm×the width 10 mm, and the thickness of 20 μm to 500 μm.

In addition, a preferred embodiment of the indentation is as follows.Specifically, as the above indentation, when the Al foil is used as thefoil 13 of the first valve metal, it is preferable, for example, a diemade of SiC in which plural micro bumps are formed is pressed on thesurface of the Al foil at a lattice constant 70 nm of bumps formingtriangular lattices in a two-dimensional triangular lattice shape,however, it is not limited to this, and it is also preferable that, forexample, a die having a circular-cone shape having a single micro bumpis used and pressed at plural times so as to be a predeterminedarrangement.

A preferred embodiment of the anodic oxidation is as follows.Specifically, it is preferable that, for example, the anodic oxidationis performed in a condition that oxidation voltage is fixed to 25V in ananodic oxidation bath (H₂SO₄ of 0.3M, temperature 10° C.) so that theconcave portions 15 a 2 belonging to the first group have apredetermined depth respectively.

Next, a preferred embodiment of the dielectric layer “d” is as follows.Specifically, it is preferable that the dielectric layer “d” is formedin a porous-plate state by performing anodic oxidation to the foil 13 ofthe first valve metal 1. It is preferable that the layer is an oxide ofthe first valve metal 1 as in the dielectric substance 14, for example,Al₂O₃ which is an oxide of Al. In this case, the permittivity of thedielectric layer “d” is approximately 10. It is not limited to this, andit is also preferable to apply oxides of the above other valve metalssuch as Ta, Nb, Ti, Hf, W, and V.

Next, a preferred embodiment of the dielectric substance 14 is asfollows. Specifically, it is preferable that the dielectric substance 14is formed in a porous-plate state by performing anodic oxidation to thefoil 13 of the first valve metal. It is preferable that the dielectricsubstance is an oxide of the first valve metal, for example, Al₂O₃ whichis an oxide of Al, however, it is not limited to this, and it is alsopreferable to apply oxides of other valve metals such as Ta, Nb, Ti, Hf,W, and V.

Next, a preferred embodiment of the seed-layers is as follows.Specifically, it is preferable that the seed-layer S is Cu, however, itis not limited to this, and it is also preferable to apply elementalsubstances of Sn, Ag, Au, Zn, Cr, Pt, Ni or alloys thereof. It ispreferable that the seed-layers is formed by electroless deposition atinner surfaces of the concave portions 15 a 2 belonging to the firstgroup and inner surfaces of the concave portions 15 b 2 belonging to thesecond group from one principal surface 14 a side of the porous-platedielectric substance 14. The thickness thereof is preferable to be 1 nmto 10 nm.

A preferred embodiment of etching performed to the other principalsurface 14 b side of the dielectric substance 14 is as follows.Specifically, it is preferable to apply chemical etching as the etching,in which the other principal surface 14 b side of the dielectricsubstance 14 is allowed to be dipped into, for example, an HgC12solution.

Next, preferred embodiments of the first pillar-shaped electrodes 16 aand the second pillar-shaped electrode 16 b are as follows.Specifically, it is preferable that the pillar-shaped electrodes 16 a,16 b are Cu as same as the hide electrodes 12 a, 12 b, however, it isnot limited to this, and it is also preferable to apply elementalsubstances of Sn, Ag, Au, Zn, Cr, Pt, and Ni or alloys thereof.Additionally, the pillar-shaped electrodes 16 a, 16 b are preferable tobe formed on the seed-layer S of the pores 15 a 3, 15 b 3 belonging tothe first and second groups by electrolytic plating. The diameter of thepillar-shaped electrodes 16 a, 16 b is preferable to be several nm toseveral hundred nm. The height of the pillar-shaped electrodes 16 a, 16b are not particularly limited and preferable to be several nm toseveral μm, more preferably to be several ten nm to several μm.

A preferred embodiment of the first hide electrode 12 a and the secondhide electrode 12 b is as follows. Specifically, it is preferable thatthe hide electrodes 12 a, 12 b are Cu, however, it is not limited tothis, and it is also preferable to apply elemental substances of Sn, Ag,Au, Zn, Cr, Pt and Ni or alloys thereof. The hide electrodes 12 a, 12 bare preferable to be formed in a planar shape so as to fill oneprincipal surface 14 a and the other principal surface 14 b of theporous-plate dielectric substance 14 respectively by means such aselectroless deposition, electolytic plating or vacuum deposition, andthe thickness thereof is preferably 1 μm to 100 μm.

Next, a preferred embodiment of the electroconductive polymer layers 17a, 17 b are as follows. Specifically, it is preferable that theelectroconductive polymer layers 17 a, 17 b are formed byelectropolymerization by feeding power to the dielectric substance 14 ina water solution including a monomer and an electrolyte so as to fillthe pores 15 a 3 belonging to the first group and the pores 15 b 3belonging to the second group.

As the monomer, for example, pyrrole (concentration 0.2 mol/l) ispreferable, however, it is not limited to this, and for example,polyaniline, polyethylene dioxy thiophene, triazine thiol, poly (thienylpyrrole) and the like are preferable.

As the electrolyte, for example, a water solution of p-sodium sulfonate(PTS) (concentration 0.3 mol/l) is preferable.

The thickness of the electroconductive polymer layers 17 a, 17 b arepreferably, for example, 100 nm to 10 μm.

Additionally, the formation of the second pillar-shaped electrode 16 band the second hide electrode 12 b are not limited to the electrolyticplating method, and the electroless deposition is also preferable, andfurther, a vacuum deposition method and the like can be used.

A preferred embodiment of the organic insulator layers 18 a, 18 b is asfollows. Specifically, it is preferable to pyrolyze and insulate theelectroconductive polymer layers 17 a, 17 b by increasing temperature ofthe dielectric substance 14 in which the electroconductive polymerlayers 17 a, 17 b are formed to a decomposition temperature of themonomer in the electroconductive polymer layers 17 a, 17 b(approximately 300° C. in the case of pyrrole), for example, in the airand holding the temperature for an hour.

Next, a preferred embodiment of the insulator layer 18 is as follows.Specifically, it is preferable that the insulator layer 18 is an organicinsulator obtained by pyrolyzing the electroconductive polymer layer, aTiO₂ film obtained by pyrolyzing a TiO₂ electrodeposited film, an SiO₂electrodeposited film, an SiO₂ layer which is wet-accumulated on anSn—Pd plated layer, an insulating resin layer and the like, and an oxidelayer of the second valve metal and air space are also preferable.

Furthermore, a preferred embodiment of the voltage application is asfollows. Specifically, it is preferable that, for example, voltage of25V is applied as the voltage application between the first hideelectrode 12 and the second hide electrode 12 b, and for example,current is allowed to flow at short-circuit points such as theseed-layer remaining in the organic insulator layers 18 a, 18 b, then,accordingly the short-circuit points are burned off to thereby reduceleakage current.

In the present disclosure where conditions and/or structures are notspecified, the skilled artisan in the art can readily provide suchconditions and/or structures, in view of the present disclosure, as amatter of routine experimentation. Further, the anodic oxidationtechnology disclosed in U.S. patent application Ser. No. 12/139,444,filed Jun. 13, 2008, and U.S. patent application Ser. No. 12/139,450,filed Jun. 13, 2008, by the same assignee as in the present applicationcan be used and modified, the disclosure of which is herein incorporatedby reference in their entirety.

The present invention will be explained in detail with reference tospecific examples which are not intended to limit the present invention.The numerical numbers applied in specific examples may be modified by arange of at least ±50%, wherein the endpoints of the ranges may beincluded or excluded.

Example 1

First, the foil 13 made of Al having the length of 3.0 mm, the width of1.5 mm and the thickness of 200 μm was prepared, the indentation wasperformed at plural positions by using the die 11 a made of SiC whichwas 10 nm in diameter to form micro concave portions at a latticeconstant 105 nm of bumps forming triangular lattices in atwo-dimensional triangular lattice shape on one principal surface of thefoil 13.

Next, anodic oxidation was performed in a condition that oxidationvoltage was fixed to 25V, allowing one principal surface of the foil 13to be dipped into an anodic oxidation bath (H₂SO₄ of 0.3M, temperature10° C.) to thereby form the porous dielectric substance 14 includingconcave portions 15 a 2 belonging to the first group and concaveportions 15 b 2 belonging to the second group having an inside diameter30 nm respectively and different depths. Next, the seed-layer S wasformed at inner surfaces of concave portion 15 a 2, 15 b 2 belonging tothe first and second groups by electroless deposition. Next, bottomportions of the concave portions 15 a 2 belonging to the first group wasremoved by chemical etching by using the HgCl₂ solution to form pores 15a 3 belonging to the first group. Next, the first pillar-shapedelectrodes 16 a were formed in the pores 15 a 3 belonging to the firstgroup by Cu electrolytic plating by feeding power to the seed-layer S atinner surfaces of the pores 15 a 3 belonging to the first group, leavingtips of the pores 15 a 3 of the other principal surface 14 b side of thedielectric substance 14 as well as the first hide electrode 12 a wasformed on one principal surface 14 a of the porous plate dielectricsubstance 14. Next, bottom portions of the concave portions 15 b 2belonging to the second group of the dielectric substance 14 wereremoved by chemical etching in the same manner as the above to formpores 15 b 3 belonging to the second group. Next, power was fed again inthe water solution of pyrrole (concentration 0.2 mol/l) as a monomer andsodium p-toluenesulfonate (PTS) (concentration 0.3 mol/l) as anelectrolyte to form the electroconductive polymer layers 17 a, 17 b madeof polypyrrole so as to fill pores belonging to the first and secondgroups by electropolymerization. Next, the second pillar-shapedelectrodes 16 b were formed inside the second pores 15 b 3 by the Cuelectrolytic plating again as well as the second hide electrode 12 b wasformed on the other principal surface 14 b of the porous platedielectric substance 14. Next, the temperature was allowed to beincreased to 300° C. which is a decomposition temperature of polypyrrolein the atmosphere, held for one hour to allow the electroconductivepolymer layers 17 a, 17 b made of polypyrrole to be pyrolyzed to loseconductivity to form the organic insulator layers 18 a, 18 b having thethickness of 3 μm respectively. Next, voltage (alternatingcurrent/direct current) of 25V was applied between the first hideelectrodes 12 a and the second hide electrode 12 b and short-circuitpoints between the counter electrodes such as the seed-layer S remainingin the organic insulator layer 18 a, 18 b were burned off to obtain thecapacitor element 10 having the length of 1.5 mm, the width of 1.5 mmand the thickness of 0.2 mm, in which leakage current was reduced. Inthe capacitor element 10, the first pillar-shaped electrode 16 a and thesecond pillar-shaped electrodes 16 b respectively had a diameter of 30nm, the pitch between the first pillar-shaped electrodes 16 a and thesecond pillar-shaped electrodes 16 b was 70 nm, and the linear dimensionof a portion in which the first pillar-shaped electrode 16 a and thesecond pillar-shaped electrode 16 b were opposed to each other was 100μm.

Concerning the obtained capacitor element 10, electrostatic capacity wasmeasured by using an LCR meter 4263B manufactured by Agilent as well asvoltage proof was measured by using high-resistance meter R8340manufactured by ADVANTEST CORPORATION. As a result, the capacitor hadinitial performance in which electrostatic capacity was 0.25 mF andvoltage proof was 30V, which had high CV product as compared with theconventional electrolytic capacitor having the same size in whichelectrostatic capacity was 47 μF and voltage proof was 4V.

The first embodiment of the method of manufacturing the capacitorelement included in the invention is not limited to one example asdescribed above, and for example, can be modified as follows.

FIG. 7 is a flowchart showing an outline of another example ofmanufacturing process in the method of manufacturing the capacitorelement according to the first embodiment of the invention.

Specifically, the above example includes the process of m: burning offshort-circuit points between the counter electrodes by, for example,applying voltage after the process of l: insulating theelectroconductive polymer layers by, for example, pyrolysis. Whereas, inthe modification example, it is also preferable that l′: theelectroconductive polymer layers are insulated and the short-circuitpoints are burned off at the same time by, for example, applying voltageunder high temperature. The method of manufacturing the capacitorelement according to the embodiment can be all performed by wetprocesses, which can provide a reasonable capacitor element.

Additionally, the example has a characteristic that the leakage currentcan be controlled by burning-off.

Next, a second embodiment of the capacitor element included in theinvention will be explained. An insulator layer of a capacitor element120 of the embodiment is made of an organic insulator layer obtained byinsulating, for example, an electroconductive polymer layer by pyrolysisin the same way as the above first embodiment, therefore, explanationthereof will be omitted.

Next, a second embodiment of a method of manufacturing the capacitorelement included in the invention will be explained with reference toFIG. 8 to FIG. 12. FIG. 8 is a flowchart showing an outline of oneexample of manufacturing process in a method of manufacturing thecapacitor element 120 according to the embodiment. FIG. 9 and FIG. 10are longitudinal cross-sectional views corresponding to FIG. 1B forexplaining respective processes of the manufacturing process, which iscontinued from FIG. 4A to FIG. 4E of the above first embodiment to FIG.9G2 to FIG. 9I2, FIG. 10K21 to FIG. 10F22 in order. Note that signs putto respective processes in FIG. 8 correspond to signs in parentheses ofFIG. 9 G2 to FIG. 9I2 and FIG. 10 K21 to FIG. 10F22.

The outline of the method of manufacturing the capacitor elementaccording to the embodiment is as follows as shown in FIG. 8, a: a foil13 of a first valve metal is prepared, b, (d): micro concave portions 15a 1, (15 b 1) are formed on one principal surface of the foil 13 by, forexample, indentation. Next, c, e: a dielectric substance 14 includingconcave portions 15 a 2 belonging to a first group and concave portions15 b 2 belonging to a second group which are different depths in the oneprincipal surface 13 a of the foil 13 is formed by, for example, anodicoxidation. Next, g2: bottom portions of concave portions 15 a 2belonging to the first group of the dielectric substance 14 are removedby, for example, chemical etching to form pores 15 a 3 belonging to thefirst group. Next, f21: a first feeding power electrode 12 a′ is formedon one principal surface 14 a of the dielectric substance 14 by, forexample, electroless deposition. Next, h2: first pillar-shapedelectrodes 16 a are formed in the pores 15 a 3 belonging to the firstgroup, leaving tips of the pores 15 a 3 of the other principal surface14 b side of the dielectric substance 14 by, for example, electrolyticplating. Next, j21: an insulator layer 128 a is formed in the pores 15 a3 belonging to the first group so as to fill tips “t” of the firstpillar-shaped electrodes 16 a. Next, i2: the first feeding powerelectrode 12 a′ and bottom portions of concave portions 15 b 2 belongingto the second group are removed by, for example, chemical etching toform pores 15 b 3 belonging to the second group. Next, k21: a secondhide electrode 12 b is formed on the other principal surface 14 b of thedielectric substance 14 by, for example, electroless deposition. Next,k22: second pillar-shaped electrodes 16 b are formed in the pores 15 b 3belonging to the second group, leaving tips of the pores 15 b 3 of oneprincipal surface 14 a side of the dielectric substance 14. Next, j22:an insulator layer 128 b is formed in the pores 15 b 3 belonging to thesecond group so as to fill the tips “t” of the second pillar-shapedelectrodes 16 b, Next, f22: a first hide electrode 12 a connecting tobase ends “b” of the first pillar-shaped electrode 16 a on one principalsurface 14 a of the dielectric substance 14 is formed.

Next, points in which the method of manufacturing the capacitor element120 according to the embodiment is different from the method ofmanufacturing the capacitor element 10 of the previous first embodimentwill be described. In the previous embodiment, the insulator layer 18 isformed at the same time on the tips “t” of the first pillar-shapedelectrodes 16 a in the pores 15 a 3 belonging to the first group andbottom portions of the pores 15 b 3 belonging to the second group,however, in the present embodiment, the insulator layer 128 a on thetips “t” of the first pillar-shaped electrodes 16 a in the pores 15 a 3belonging to the first group and the insulator layer 128 b on the tips“t” of the second pillar-shaped electrodes 16 b in the pores 15 b 3belonging to the second group are formed in processes which areindependent from each other in the manufacturing process. The method ofmanufacturing the capacitor element according to the embodiment can beall performed by wet processes, which enables a reasonable capacitorelement to be provided.

Next, one example of the method of manufacturing the capacitor element120 according to the embodiment will be shown in FIG. 11 and FIG. 12.FIG. 11 is a flowchart showing an outline of one example ofmanufacturing process according to the embodiment. FIG. 12J211 to FIG.12J222 are longitudinal cross-sectional views for explaining formingprocesses of the insulating layer 18 in the manufacturing process. Notethat signs put to respective processes in FIG. 11 correspond to signs inparentheses of FIG. 12J211 to FIG. 12J222.

Specifically, the process j21: the insulating layer 128 a is formed ontips “t” of the first pillar-shaped electrodes 16 a according to theembodiment corresponds to a process J211: an electroconductive layer 127a is formed on the tips “t” of the first pillar-shaped electrodes 16 aby, for example, electropolymerization, using the first feeding powerelectrode 12 a′ as a feeding power layer, then, a process j212: theinsulator layer 128 a is formed by insulating an electroconductivepolymer layer 127 a by, for example, pyrolysis. Similarly, the processj22: the insulator layer 128 b is formed on tips ‘t’ of the secondpillar-shaped electrodes 16 b in the embodiment corresponds to a processJ221: an electroconductive polymer layer 127 b is formed on tips “t” ofthe second pillar-shaped electrodes 16 b by, for example,electropolymerization, using the second hide electrode 12 b as a feedingpower layer, then, a process J222; the insulator layer 128 b is formedby insulating the electroconductive polymer layer 127 b.

Next, a preferred embodiment of the first feeding power electrode 12 a′will be explained. Specifically, as materials for the first feedingpower electrode 12 a′, metals (for example, at least one kind selectedfrom Cu, Ni, Cr, Ag, Au, Pd, Fe, Sn, Pt, Ir, Rh, Ru, Al) can be used.The thickness of the first feeding power electrode 12 a′ is preferablyseveral ten nm to several μm. As a method of forming the first feedingpower electrode 12 a′, PVD, CVD and the like can be used in addition toelectroless deposition.

Example 2

First, the foil 13 made of Al having the length of 3.0 mm, the width of1.5 mm and the thickness of 200 μm was prepared, and the porous platedielectric substance 14 including the concave portions 15 a 2 belongingto the first group and the concave portions 15 b 2 belonging to thesecond group having different depths was formed in the same manner asthe previous Example 1.

Next, bottoms of the concave portions 15 a 2 belonging to the firstgroup were removed by chemical etching using an HgCl₂ solution to formpores 15 a 3 belonging to the first group. Next, the first feeding powerelectrode 12 a′ made of Ni was formed on one principal surface 14 a byelectroless deposition. Next, the first pillar-shaped electrodes 16 awere formed in pores 15 a 3 belonging to the first group by Cuelectrolytic plating by feeding the first feeding power electrodes 12a′, leaving tips of the pores 15 a 3 of the other principal surface 14 bside of the dielectric substance 14. Next, the electroconductive polymerlayer 127 a made of electrodeposition polyimide resin was formed on tips“t” of the first pillar-shaped electrodes 16 a in the pores 15 a 3belonging to the first group so as to fill the pores 15 a 3, then, heattreatment was performed at 300° C. for 1 hour to lose conductivity bypyrolysis, thereby forming an insulator layer 128 a made of an organicinsulator having the thickness of 3 μm. Next, pores 15 b 3 belonging tothe second group were formed by removing the first feeding powerelectrode 12 a′ and bottoms of concave portions 15 b 2 belonging to thesecond group by chemical etching using the HgCl₂ solution. Next, thesecond hide electrode 12 b made of Ni was formed on the other principalsurface 14 b of the dielectric substance 14 by electroless deposition.Next, the second pillar-shaped electrodes 16 b were formed in the pores15 b 3 belonging to the second group by Cu electrolytic plating, usingthe hide electrode 12 b as a feeding power layer, leaving tips of thepores 15 b 3 of one principal surface 14 a side of the dielectricsubstance 14. Next, in the same manner as described above, theelectroconductive polymer layer 127 b made of electrodepositionpolyimide resin was formed on tips “t” of the second pillar-shapedelectrodes 16 b in the pores 15 b 3 belonging to the second group so asto fill the pores 15 b 3, then, heat treatment was performed to loseconductivity by pyrolysis, thereby forming an insulator layer 128 b madeof an organic insulator having the thickness of 3 μm. Next, a first hideelectrode 12 a was formed on one principal surface 14 a of thedielectric substance 14 by Cu electrolytic plating so as to touch baseends “b” of the first pillar-shaped electrodes 16 a to obtain thecapacitor element 120. In the capacitor element 120, as in the capacitorelement 10 of the Example 1, the first pillar-shaped electrode 16 a andthe second pillar-shaped electrode 16 b respectively had 30 nm indiameter, the pitch between the first pillar-shaped electrode 16 a andthe second pillar-shaped electrode 16 b was 70 nm, the linear dimensionof a portion in which the first pillar-shaped electrode 16 a and thesecond pillar-shaped electrode 16 b were opposed to each other was 100μm.

Concerning the obtained capacitor element 120, electrostatic capacitywas measured by using an LCR meter 4263B manufactured by Agilent as wellas voltage poof was measured by using high-resistance meter R8340manufactured by ADVANTEST CORPORATION. As a result, the capacitor hadinitial performance in which electrostatic capacity was 0.25 mF andvoltage proof was 30V in the same manner as the Example 1.

Next, a third embodiment of the capacitor element included in theinvention will be explained. A capacitor element 130 of the embodimentis different from the capacitor elements of the previous first andsecond embodiments in a point that the insulator layer is made of a TiO₂film. Since other configurations are same as the previous firstembodiment, explanation thereof is omitted. Note that the capacitorelement of the present embodiment has a characteristic that insulationperformance is excellent.

Next, a third embodiment of a method of manufacturing the capacitorelement included in the invention will be explained with reference ofFIG. 13 and FIG. 14. FIG. 13 is a flowchart showing an outline of oneexample of manufacturing process in the method of manufacturing thecapacitor element 130 according to the embodiment. FIG. 14J311 to FIG.14J322 are longitudinal cross-sectional views for explaining formingprocesses of insulator layers in the manufacturing process. Signs put torespective processes in FIG. 13 correspond to signs in parentheses ofFIG. 14J311 to FIG. 14J322.

The outline of the method of manufacturing the capacitor element 130 ofthe present embodiment is as follows as shown in FIG. 13, a: a foil 13of a first valve metal is prepared, b, (d): micro concave portions 15 a1 (15 b 1) are formed on one principal surface of the foil 13 by, forexample, indentation. Next, c, e: a dielectric substance 14 includingconcave portions 15 a 2 belonging to a first group and concave portions15 b 2 belonging to a second group having different depths in the oneprincipal surface 13 a of the foil 13 is formed by, for example, anodicoxidation. Next, g3: bottom portions of the concave portions 15 a 2belonging to the first group of the dielectric substance 14 are removedby, for example, chemical etching to form pores 15 a 3 belonging to thefirst group. Next, f31: a first feeding power electrode 12 a′ is formedon one principal surface 14 a of the dielectric substance 14 by, forexample, electroless deposition. Next, h3: first pillar-shapedelectrodes 16 a are formed in the pores 15 a 3 belonging to the firstgroup by, for example, electrolytic plating, leaving tips of the pores15 a 3 of the other principal surface 14 b side of the dielectricsubstance 14. Next, as a process corresponding to the former insulatinglayer forming process j21 in the previous second embodiment, j311: aTiO₂ electrodeposited film 137 a is formed by, for example, electrolyticplating on the tips “t” of the first pillar-shaped electrodes 16 a inthe pores 15 a 3 belonging to the first group so as to fill the pores 15a 3, then, j312: the TiO₂ electrodeposited film 137 a is insulated by,for example, heat treatment to form an insulator layer 138 a made of theTiO₂ film. Next, i3: the first feeding power electrode 12 a′ and bottomportions of the concave portions 15 b 2 belonging to the second groupare removed by chemical etching to form pores 15 b 3 belonging to thesecond group. Next, k31: a second hide electrode 12 b is formed on theother principal surface 14 b of the dielectric substance 14 by, forexample, electroless deposition. Next, k32: second pillar-shapedelectrodes 16 b are formed in the pores 15 b 3 belonging to the secondgroup, leaving tips of the pores 15 b 3 of one principal surface 14 aside of the dielectric substance 14. Next, as a process corresponding tothe latter insulating layer forming process j22 of the previous secondembodiment, j321: a TiOs electrodeposited film 137 b is formed on thetips “t” of the second pillar-shaped electrodes 16 b in the pores 15 b 3belonging to the second group so as to fill the pores 15 b 3, then,j322: the TiO₂ electrodeposited film 137 a is insulated to form aninsulator layer 138 b made of the TiO₂ film. Next, f32: the first hideelectrode 12 a connected to the base ends “b” of the first pillar-shapedelectrodes 16 a on one principal surface 14 a of the dielectricsubstance 14 is formed.

In the method of manufacturing the capacitor element according theembodiment, in the same manner as the previous second embodiment, theinsulator layer 138 a on the tips “t” of the first pillar-shapedelectrodes 16 a in the pores 15 a 3 belonging to the first group and theinsulator layer 138 b on the tips “t” of the second pillar-shapedelectrodes 16 b in the pores 15 b 3 belonging to the second group areformed in processes which are independent from each other in themanufacturing process.

Next, a preferred embodiment of the TiO₂ electrodeposited film isexplained. Specifically, as the TiO₂ electrodeposited film, a titaniumoxide film obtained by performing electrolytic plating in a titaniumchloride solution can be used. It is preferable that the thickness ofthe TiO₂ electrodeposited film is approximately several ten nm toseveral μm.

Next, a preferred embodiment of the TiO₂ film is explained.Specifically, it is preferable that the thickness of the TiO₂ film isseveral ten nm to several μm. In the method of manufacturing thecapacitor element according to the embodiment has a characteristic thatthe insulating film can be easily formed.

Next, a preferred embodiment of the heat treatment is explained.Specifically, it is preferable that the heat treatment is performed inthe oxygen atmosphere, for example, at 450° C. for approximately 30minutes.

Example 3

First, the foil 13 made of Al having the length of 3.0 mm, the width of1.5 mm and the thickness of 200 μm was prepared, and the porous platedielectric substance 14 including concave portions 15 a 2 belonging tothe first group and concave portions 15 b 2 belonging to the secondgroup having different depths was formed in the same manner as theprevious Example 1.

Next, in the same manner as the Example 2, the pores 15 a 3 belonging tothe first group, the first feeding power electrode 12 a′ and firstpillar-shaped electrodes 16 a were formed. Next, the electrodepositedTiO₂ film 137 a was formed on tips “t” of the first pillar-shapedelectrodes 16 a in the pores 15 a 3 belonging to the first group so asto fill the pores 15 a 3 by performing the electrolytic plating in atitanium chloride solution, then, the insulator layer 138 a made of TiO₂having the thickness of 7.5 μm was formed by performing heat treatmentat 450° C. for 30 minutes. Next, in the same manner as the Example 2,pores 15 b 3 belonging to the second group, a second hide electrode 12 band second pillar-shaped electrodes 16 b were formed. Next, theinsulating layer 138 b made of TiO₂ having the thickness of 7.5 μm wasformed in the same manner as described above. Next, the first hideelectrode 12 a was formed on one principal surface 14 a of thedielectric substance 14 by Cu electrolytic plating so as to touch baseends “b” of the first pillar-shaped electrodes 16 a to obtain thecapacitor element 130. In the capacitor element 130, as in the capacitorelement 10 of the Example 1, the first pillar-shaped electrode 16 a andthe second pillar-shaped electrode 16 b respectively had 30 nm indiameter, the pitch between the first pillar-shaped electrode 16 a andthe second pillar-shaped electrode 16 b was 70 nm, the linear dimensionof a portion in which the first pillar-shaped electrode 16 a and thesecond pillar-shaped electrode 16 b were opposed to each other was 100μm.

Concerning the obtained capacitor element 130, electrostatic capacitywas measured by using an LCR meter 4263B manufactured by Agilent as wellas voltage poof was measured by using high-resistance meter R8340manufactured by ADVANTEST CORPORATION. As a result, the capacitor hadinitial performance in which electrostatic capacity was 0.25 mF andvoltage proof was 30V in the same manner as the Example 1.

Next, a fourth embodiment of the capacitor element included in theinvention will be explained. A capacitor element 140 of the embodimentis different from the capacitor elements of the previous first to thirdembodiments in a point that the insulator layer is made of SiO₂ film.Since other configurations are the same as the previous firstembodiment, explanation thereof is omitted. Note that the capacitorelement 140 of the present embodiment has a characteristic that thermalstability is excellent.

Next, a fourth embodiment of a method of manufacturing the capacitorelement included in the invention will be explained with reference toFIG. 15. FIG. 15 is a flowchart showing an outline of one example inmanufacturing process of the method of manufacturing the capacitorelement 140 according to the embodiment.

The outline of the method of manufacturing the capacitor element 140 ofthe present embodiment is as follows as shown in FIG. 15, a: a foil 13of a first valve metal is prepared, b, (d): micro concave portions 15 a1 (15 b 1) are formed on one principal surface 13 a of the foil 13 by,for example, indentation. Next, c, e: a dielectric substance 14including concave portions 15 a 2 belonging to a first group and concaveportions 15 b 2 belonging to a second group having different depths inthe one principal surface 13 a of the foil 13 is formed by, for example,anodic oxidation. Next, g4: bottom portions of the concave portions 15 a2 belonging to the first group of the dielectric substance 14 areremoved by, for example, chemical etching to form pores 15 a 3 belongingto the first group. Next, f41: a first feeding power electrode 12 a′ isformed on one principal surface 14 a of the dielectric substance 14 by,for example, electroless deposition. Next, h4: first pillar-shapedelectrodes 16 a are formed in the pores 15 a 3 belonging to the firstgroup by, for example, electrolytic plating, leaving tips of the pores15 a 3 of the other principal surface 14 b side of the dielectricsubstance 14. Next, as a process corresponding to the former insulatinglayer forming process j21 in the previous second embodiment, j41: aninsulator layer 148 a made of an SiO₂ layer is formed by, for example,electrolytic plating on the tips “t” of the first pillar-shapedelectrodes 16 a in the pores 15 a 3 belonging to the first group so asto fill the pores 15 a 3. Next, i4: the first feeding power electrode 12a′ and bottom portions of concave portions 15 b 2 belonging to thesecond group are removed by, for example, chemical etching to form pores15 b 3 belonging to the second group. Next, k41: a second hide electrode12 b is formed on the other principal surface 14 b of the dielectricsubstance 14 by, for example, electroless deposition. Next, k42: secondpillar-shaped electrodes 16 b are formed in the pores 15 b 3 belongingto the second group, leaving tips of the pores 15 b 3 of one principalsurface 14 a side of the dielectric substance 14. Next, as a processcorresponding to the latter insulating film forming process j22 of theprevious second embodiment, j42: an insulator layer 148 b made of anSiO₂ layer is formed on the tips “t” of the second pillar-shapedelectrodes 16 b in the pores 15 b 3 belonging to the second group so asto fill the pores 15 b 3. Next, f42: a first hide electrode 12 atouching base ends “b” of the first pillar-shaped electrodes 16 a on oneprincipal surface 14 a of the dielectric substance 14 is formed.

In the method of manufacturing the capacitor element 140 according theembodiment, in the same manner as the previous second embodiment, theinsulator layer 148 a on the tips “t” of the first pillar-shapedelectrodes 16 a in the pores 15 a 3 belonging to the first group and theinsulator layer 148 b on the tips “t” of the second pillar-shapedelectrodes 16 b in the pores 15 b 3 belonging to the second group areformed in processes which are independent from each other in themanufacturing process.

Next, a preferred embodiment of the SiO₂ layer is explained.Specifically, as the SiO₂ layer, a silicon oxide film obtained byperforming electrolytic plating processing in an ammonium fluorosilicatesolution can be used. The thickness of the SiO₂ layer is preferablyseveral ten nm to several μm. The method of manufacturing the capacitorelement according to the embodiment has a characteristic that theprocess is simple.

Example 4

First, the foil 13 made of Al having the length of 3.0 mm, the width of1.5 mm and the thickness of 200 μm was prepared, and the porous platedielectric substance 14 including concave portions 15 a 2 belonging tothe first group and concave portions 15 b 2 belonging to the secondgroup having different depths was formed in the same manner as theprevious Example 1.

Next, in the same manner as the Example 2, the pores 15 a 3 belonging tothe first group, a first feeding power electrode 12 a′ and firstpillar-shaped electrodes 16 a were formed. Next, the insulator film 148a made of an SiO₂ film having the thickness of 1.5 μm was formed on tips“t” of the first pillar-shaped electrodes 16 a in the pores 15 a 3belonging to the first group so as to fill the pores 15 a 3 byperforming electrolytic plating in an ammonium fluorosilicate solution.Next, in the same manner as the Example 2, the pores 15 b 3 belonging tothe second group, the second hide electrode 12 b and the secondpillar-shaped electrodes 16 b were formed. Next, in the same manner asdescribed above, the insulator film 148 b made of a SiO₂ film having thethickness of 1.5 μm was formed. Next, the first hide electrode 12 a wasformed on one principal surface 14 a of the dielectric substance 14 soas to touch base ends “b” of the first pillar-shaped electrodes 16 a byCu electrolytic plating to obtain the capacitor element 140. In thecapacitor element 140, as in the capacitor element 10 of the Example 1,the first pillar-shaped electrode 16 a and the second pillar-shapedelectrode 16 b respectively had 30 nm in diameter, the pitch between thefirst pillar-shaped electrode 16 a and the second pillar-shapedelectrode 16 b was 70 nm, the linear dimension of a portion in which thefirst pillar-shaped electrode 16 a and the second pillar-shapedelectrode 16 b were opposed to each other was 100 μm.

Concerning the obtained capacitor element 140, electrostatic capacitywas measured by using an LCR meter 4263B manufactured by Agilent as wellas voltage proof was measured by using high-resistance meter R8340manufactured by ADVANTEST CORPORATION. As a result, the capacitor hadinitial performance in which electrostatic capacity was 0.25 mF andvoltage proof was 30V in the same manner as the Example 1.

Next, a fifth embodiment of the capacitor element included in theinvention will be explained. A capacitor element 150 of the embodimentis the same as the capacitor element of the previous fourth embodimentin a point that the insulator layer is made of an SiO₂ film. Since otherconfigurations are the same as the capacitor element 10 of the previousfirst embodiment, explanation thereof is omitted. Note that thecapacitor element 150 of the present embodiment has a characteristicthat thermal stability is excellent as in the capacitor element 140 ofthe fourth embodiment.

Next, a fifth embodiment of a method of manufacturing the capacitorelement included in the invention will be explained with reference ofFIG. 16 and FIG. 17. FIG. 16 is a flowchart showing an outline of oneexample of manufacturing process of the method of manufacturing thecapacitor element 150 according to the embodiment. FIG. 17J511 to FIG.17J522 are longitudinal cross-sectional views for explaining formingprocesses of insulator layers in the manufacturing process. Signs put torespective processes in FIG. 16 correspond to signs in parentheses ofFIG. 17J511 to FIG. 17J522.

The outline of the method of manufacturing the capacitor element 150 ofthe present embodiment is as follows as shown in FIG. 16, a: a foil 13of a first valve metal is prepared, b, (d): micro concave portions 15 a1 (15 b 1) are formed on one principal surface 13 a of the foil 13 by,for example, indentation. Next, c, e: a dielectric substance 14including concave portions 15 a 2 belonging to a first group and concaveportions 15 b 2 belonging to a second group having different depths inthe one principal surface 13 a of the foil 13 is formed by, for example,anodic oxidation. Next, g5: bottom portions of the concave portions 15 a2 belonging to the first group of the dielectric substance 14 areremoved by, for example, chemical etching to form pores 15 a 3 belongingto the first group. Next, f51: a first feeding power electrode 12 a′ isformed on one principal surface 14 a of the dielectric substance 14 by,for example, electroless deposition. Next, h5: first pillar-shapedelectrodes 16 a are formed in the pores 15 a 3 belonging to the firstgroup by, for example, electrolytic plating, leaving tips of the pores15 a 3 of the other principal surface 14 b side of the dielectricsubstance 14. Next, as a process corresponding to the former insulatinglayer forming process j21 in the previous second embodiment, j511: anSn—Pd plating layer 157 a is formed by, for example, electrolyticplating on the tips “t” of the first pillar-shaped electrodes 16 a inthe pores 15 a 3 belonging to the first group so as to fill the pores 15a 3, then, j512: an insulator layer 158 a made of an SiO₂ layer isformed on the Sn—Pd plating layer 157 a by wet accumulation so as tofill the pores 15 a 3. Next, i5: the first feeding power electrode 12 a′and bottom portions of the concave portions 15 b 2 belonging to thesecond group are removed by, for example, chemical etching to form pores15 b 3 belonging to the second group. Next, k51: a second hide electrode12 b is formed on the other principal surface 14 b of the dielectricsubstance 14 by, for example, electroless deposition. Next, k52: secondpillar-shaped electrodes 16 b are formed in the pores 15 b 3 belongingto the second group, leaving tips of the pores 15 b 3 of one principalsurface 14 a side of the dielectric substance 14. Next, as a processcorresponding to the latter insulating film forming process j22 of theprevious second embodiment, J521: an Sn—Pd plating layer 157 b is formedon tips “t” of the second pillar-shaped electrodes 16 b in the pores 15b 3 belonging to the second group so as to fill the pores 15 b 3, then,j522: an insulator layer 158 b made of an SiO₂ layer is formed on theSn—Pd plating layer 157 b by wet accumulation. Next, f52: a first hideelectrode 12 a touching base ends “b” of the first pillar-shapedelectrodes 16 a is formed on one principal surface 14 a of thedielectric substance 14.

In the method of manufacturing the capacitor element 150 according theembodiment, in the same manner in the previous second embodiment, theinsulator layer 158 a on the tips “t” of the first pillar-shapedelectrodes 16 a in the pores 15 a 3 belonging to the first group and theinsulator layer 158 b on the tips “t” of the second pillar-shapedelectrodes 16 b in the pores 15 b 3 belonging to the second group areformed in processes which are independent from each other in themanufacturing process.

Next, a preferred embodiment of the Sn—Pd plating layer is explained.Specifically, the Sn—Pd plating layer can be obtained by performingelectrolytic plating in an SnCl₂ solution and a PdCl₂ solution,respectively. The thickness of the plating layer is preferably severalten nm to several μm.

Next, a preferred embodiment of the wet accumulation of the SiO₂ film isexplained. Specifically, as the wet accumulation of the SiO₂ film, asilicon oxide film obtained by electroless deposition processing in anammonium fluorosilicate solution can be used. The thickness of the layeris preferably several ten nm to several μm. The method of manufacturingthe capacitor element of the embodiment has a characteristic that theprocess is simple. The wet accumulation of the SiO₂ film is not limitedto the electroless deposition processing but the SiO₂ film can be formedby using, for example, a slurry build method.

Example 5

First, the foil 13 made of Al having the length of 3.0 mm, the width of1.5 mm and the thickness of 200 μm was prepared, and the porous platedielectric substance 14 including concave portions 15 a 2 belonging tothe first group and concave portions 15 b 2 belonging to the secondgroup having different depths was formed in the same manner as theprevious Example 1.

Next, in the same manner as the Example 2, the pores 15 a 3 belonging tothe first group, the first feeding power electrode 12 a′ and the firstpillar-shaped electrodes 16 a are formed. Next, the Sn—Pd plating layer157 a is formed on tips “t” of the first pillar-shaped electrodes 16 ain the pores 15 a 3 belonging to the first group so as to fill the pores15 a 3 by performing electrolytic plating in the SnCl₂ solution and thePdCl₂ solution, respectively. Next, the insulator layer 158 a made ofthe SiO₂ film having the thickness of 1.5 μm is formed on the Sn—Pdplating layer so as to fill the pores 15 a 3 by electroless depositionin an ammonium fluorosilicate solution. Next, in the same manner as theExample 2, pores 15 b 3 belonging to the second group, the second hideelectrode 12 b and the second pillar-shaped electrodes 16 b were formed.Next, in the same manner as described above, an insulator film 158 bmade of an SiO₂ film having the thickness of 1.5 μm was formed on theSn—Pd plating layer 157 b. Next, the first hide electrode 12 a wasformed on one principal surface 14 a of the dielectric substance 14 soas to touch base ends “b” of the first pillar-shaped electrodes 16 a byCu electrolytic plating to obtain the capacitor element 150. In thecapacitor element 150, as in the capacitor element 10 of the Example 1,the first pillar-shaped electrode 16 a and the second pillar-shapedelectrode 16 b respectively had 30 nm in diameter, the pitch between thefirst pillar-shaped electrode 16 a and the second pillar-shapedelectrode 16 b was 70 nm, the linear dimension of a portion in which thefirst pillar-shaped electrode 16 a and the second pillar-shapedelectrode 16 b were opposed to each other was 100 μm.

Concerning the obtained capacitor element 150, electrostatic capacitywas measured by using an LCR meter 4263B manufactured by Agilent as wellas voltage proof was measured by using high-resistance meter R8340manufactured by ADVANTEST CORPORATION. As a result, the capacitor hadinitial performance in which electrostatic capacity was 0.25 mF andvoltage proof was 30V in the same manner as the Example 1.

Next, a sixth embodiment of the capacitor element included in theinvention will be explained. A capacitor element 160 of the embodimentis different from the capacitor elements of the previous first to fifthembodiments in a point that the insulator layer is made of an insulatingresin layer. Since other configurations are the same as the capacitorelement 10 of the previous first embodiment, explanation thereof isomitted.

Next, a sixth embodiment of a method of manufacturing the capacitorelement included in the invention will be explained with reference ofFIG. 18 to FIG. 20. FIG. 18 is a flowchart showing an outline of oneexample of manufacturing process of the method of manufacturing thecapacitor element 160 according to the embodiment. FIG. 19 and FIG. 20are longitudinal cross-sectional views corresponding to FIG. 1B forexplaining respective processes in the manufacturing process, which iscontinued from FIG. 4A to FIG. 4E of the above first embodiment to FIG.19G6 to FIG. 19J61, FIG. 20K61 to FIG. 20F62 in order. Signs put torespective processes in FIG. 18 correspond to signs in parentheses ofFIG. 19 and FIG. 20.

The outline of the method of manufacturing the capacitor element 160 ofthe present embodiment is as follows as shown in FIG. 18, a: a foil 13of a first valve metal is prepared, b, (d): micro concave portions 15 a1 (15 b 1) are formed on one principal surface 13 a of the foil 13 by,for example, indentation. Next, c, e: a dielectric substance 14including concave portions 15 a 2 belonging to a first group and concaveportions 15 b 2 belonging to a second group having different depths inthe one principal surface 13 a of the foil 13 is formed by, for example,anodic oxidation. Next, g6: bottom portions of the concave portions 15 a2 belonging to the first group of the dielectric substance 14 areremoved by, for example, chemical etching to form pores 15 a 3 belongingto the first group. Next, f61: a first feeding power electrode 12 a′ isformed on one principal surface 14 a of the dielectric substance 14 by,for example, electroless deposition. Next, h6: first pillar-shapedelectrodes 16 a are formed in the pores 15 a 3 belonging to the firstgroup by, for example, electrolytic plating, leaving tips of the pores15 a 3 of the other principal surface 14 b side of the dielectricsubstance 14. Next, i6: the first feeding power electrode 12 a′ andbottom portions of the concave portions 15 b 2 belonging to the secondgroup are removed by, for example, chemical etching to form pores 15 b 3belonging to the second group. Next, j61: an insulator layer 168 a isformed on tips “t” of the first pillar-shaped electrodes 16 a in thepores 15 a 3 belonging to the first group so as to fill the pores 15 a3. Next, k61: a second hide electrode 12 b is formed on the otherprincipal surface 14 b of the dielectric substance 14, for example,electroless deposition. Next, k62: second pillar-shaped electrodes 16 bare formed on the second hide electrode 12 b in the pores 15 b 3belonging to the second group, leaving tips of the pores 15 b 3 of oneprincipal surface 14 a side of the dielectric substance 14. Next, j62:an insulator layer 168 b is formed on tips “t” of the secondpillar-shaped electrodes 16 b in the pores 15 b 3 belonging to thesecond group so as to fill the pores 15 b 3. Next, f62: a first hideelectrode 12 a touching base ends “b” of the first pillar-shapedelectrodes 16 a is formed on one principal surface 14 a of thedielectric substance 14.

In the method of manufacturing the capacitor element 160 according theembodiment, in the same manner as the method of manufacturing thecapacitor element in the previous second embodiment, the insulator layer168 a on the tips “t” of the first pillar-shaped electrodes 16 a in thepores 15 a 3 belonging to the first group and the insulator layer 168 bon the tips “t” of the second pillar-shaped electrodes 16 b in the pores15 b 3 belonging to the second group are formed in processes which areindependent from each other in the manufacturing process.

Next, one example of the method of manufacturing the capacitor element160 according to the embodiment is shown in FIG. 21 and FIG. 22. FIG. 21is a flowchart showing an outline of one example of manufacturingprocess of the embodiment. FIG. 22J611 and FIG. 22J612 are longitudinalcross-sectional views for explaining forming processes of an insulatorlayer in the manufacturing process.

Specifically, in j61 of the embodiment: a process of forming theinsulator layer 168 a is formed on tips “t” of the first pillar-shapedelectrodes 16 a, first, for example, the pressure in a chamber isreduced in a state in which the dielectric substance 14 is dipped into aresin solution in the chamber, j611: an insulating resin solution 167 aare buried on tips “t” of the first pillar-shaped electrodes 16 a in thepores 15 a 3 belonging to the first group and into the pores 15 b 3belonging to the second group so as to fill the pores 15 b 3. Next, forexample, reduced suction is performed from one principal surface 14 aside of the dielectric substance 14, j612: the resin solution 167 a inthe pores 15 b 3 belonging to the second group is removed. After that,heat treatment in the atmosphere at 150° C. for 30 minutes is performedand the resin solution 167 a selectively remaining only on tips “t” ofthe first pillar-shaped electrodes 16 a in the pores 15 a 3 belonging tothe first group is cured to form the insulator layer 168 a.

Next, a preferred embodiment of the insulating resin is explained.Specifically, as the insulating resin, a polyimide resin, an epoxy resinand the like are preferable. The thickness of the insulating resin ispreferably several ten nm to several μm. In the case of using thepolyimide resin as the insulating resin layer, the layer has acharacteristic that the dielectric breakdown potential frequency is highsuch as 400,000V/m. In the case of using the epoxy resin as theinsulating resin layer, the layer has a characteristic that moistureabsorption is low and durability for a reflow solder heat test is high.

Example 6

First, the foil 13 made of Al having the length of 3.0 mm, the width of1.5 mm and the thickness of 200 μm was prepared, and the porous platedielectric substance 14 including concave portions 15 a 2 belonging tothe first group and concave portions 15 b 2 belonging to the secondgroup having different depths was formed in the same manner as theprevious Example 1.

Next, bottoms of concave portion 15 a 2 belonging to the first group wasremoved by chemical etching using an HgCl₂ solution to form pores 15 a 3belonging to the first group. Next, the first feeding power electrode 12a′ made of Ni was formed on one principal surface 14 a by electrolessdeposition. Next, the first pillar-shaped electrodes 16 a were formed inthe pores 15 a 3 belonging to the first group by Cu electrolytic platingby feeding power to the first feeding power electrode 12 a′, leavingtips of the pores 15 a 3 of the other principal surface 14 b side of thedielectric substance 14. Next, the first feeding power electrode 12 a′and bottoms of concave portions 15 b 2 belonging to the second groupwere removed by chemical etching using the HgCl₂ solution to form pores15 b 3 belonging to the second group. Next, the dielectric substance 14was accommodated in a chamber in which polyimide resin solution wasstored, then, the pressure in the chamber was reduced to fill thepolyimide resin solution on tips “t” of the first pillar-shapedelectrode 16 a in the pores 15 a 3 belonging to the first group and thepores 15 b 3 belonging to the second group. Next, the resin solution inthe pores 15 b 3 belonging to the second group was removed by performingreduced suction from one principal surface 14 a side of the dielectricsubstance, then, heat treatment in the atmosphere at 150° C. for 30minutes was performed and the resin solution 167 a selectively remainingonly on tips “t” of the first pillar-shaped electrodes 16 a in the pores15 a 3 belonging to the first group was cured to form the insulatorlayer 168 a made of the insulating resin having the thickness of 75 nm.Next, the second hide electrode 12 b made of Ni was formed on the otherprincipal surface 14 b of the dielectric substance 14 by electrolessdeposition. Next, the second pillar-shaped electrodes 16 b were formedin the pores 15 b 3 belonging to the second group by Cu electrolyticplating using the hide electrode 12 b as a feeding power layer, leavingtips of the pores 15 b 3 of one principal surface 14 a side of thedielectric substance 14. Next, a solution of polyimide resin 167 b wasfilled on tips “t” of the second pillar-shaped electrodes 16 b in thepores 15 b 3 belonging to the second group so as to fill the pores 15 b3 in the same manner as described above, and heat treatment wasperformed as described above to form the insulator layer 168 b made ofthe insulating resin having the thickness of 75 nm which fills the tips“t” of the second pillar-shaped electrodes 16 b in the pores 15 b 3belonging to the second group. Next, the first hide electrode 12 a wasformed by Cu electrolytic plating in one principal surface 14 a of thedielectric substance 14 so as to touch base ends “b” of the firstpillar-shaped electrodes 16 a to obtain a capacitor element 160. In thecapacitor element 160, as in the capacitor element 10 of the Example 1,the first pillar-shaped electrode 16 a and the second pillar-shapedelectrode 16 b respectively had 30 nm in diameter, the pitch between thefirst pillar-shaped electrode 16 a and the second pillar-shapedelectrode 16 b was 70 nm, the linear dimension of a portion in which thefirst pillar-shaped electrode 16 a and the second pillar-shapedelectrode 16 b were opposed to each other was 100 μm.

Concerning the obtained capacitor element 160, electrostatic capacitywas measured by using an LCR meter 4263B manufactured by Agilent as wellas voltage proof was measured by using high-resistance meter R8340manufactured by ADVANTEST CORPORATION. As a result, the capacitor hadinitial performance in which electrostatic capacity was 0.25 mF andvoltage proof was 30V in the same manner as the Example 1.

Next, a seventh embodiment of the capacitor element included in theinvention will be explained. A capacitor element 170 of the embodimentis the same as the capacitor element of the previous sixth embodiment ina point that the insulator layer is made of an insulating resin layer,therefore, the explanation is omitted.

Next, a seventh embodiment of a method of manufacturing the capacitorelement included in the invention will be explained with reference ofFIG. 23 and FIG. 24. FIG. 23 is a flowchart showing an outline of oneexample of manufacturing process of the method of manufacturing thecapacitor element 170 according to the embodiment. FIG. 24J711 to FIG.24J722 are longitudinal cross-sectional views for explaining formingprocesses of insulator layers in the manufacturing process. Signs put torespective processes in FIG. 23 correspond to signs in parentheses ofFIG. 24.

The outline of the method of manufacturing the capacitor element 170 ofthe present embodiment is as follows as shown in FIG. 23, a: a foil 13of a first valve metal is prepared, b, (d): micro concave portions 15 a1 (15 b 1) are formed on one principal surface 13 a of the foil 13 by,for example, indentation. Next, c, e: a dielectric substance 14including concave portions 15 a 2 belonging to a first group and concaveportions 15 b 2 belonging to a second group having different depths inthe one principal surface 13 a of the foil 13 is formed by, for example,anodic oxidation. Next, g7: bottom portions of the concave portions 15 a2 belonging to the first group of the dielectric substance 14 areremoved by, for example, chemical etching to form pores 15 a 3 belongingto the first group. Next, f71: a first feeding power electrode 12 a′ isformed on one principal surface 14 a of the dielectric substance 14 by,for example, electroless deposition. Next, h7: first pillar-shapedelectrodes 16 a are formed in the pores 15 a 3 belonging to the firstgroup by, for example, electrolytic plating, leaving tips of the pores15 a 3 of the other principal surface 14 b side of the dielectricsubstance 14. Next, i7: the first feeding power electrode 12 a′ andbottom portions of the concave portions 15 b 2 belonging to the secondgroup are removed by, for example, chemical etching to form pores 15 b 3belonging to the second group. Next, as a process corresponding to theformer insulating layer forming process j61 of the sixth embodiment,j711: an insulating resin film 177 a is formed on the other principalsurface 14 b of tips “t” side of the first pillar-shaped electrodes 16 ain the pores 15 a 3 belonging to the first group, then, j712: aninsulator layer 178 a is formed on the tips “t” of the firstpillar-shaped electrodes 16 a in the pores 15 a 3 belonging to the firstgroup so as to fill the pores 15 a 3 by removing the insulating resinfilm 177 a on the other principal surface 14 b except the inside of thepores 15 a 3 belonging to the first group. Next, k71: a second hideelectrode 12 b is formed on the other principal surface 14 b of thedielectric substance 14 by, for example, electroless deposition. Next,k72: second pillar-shaped electrodes 16 b are formed in pores 15 b 3belonging to the second group, leaving tips of the pores 15 b 3 of oneprincipal surface 14 a side of the dielectric substance 14. Next, as thelatter insulating layer forming process j62 of the previous sixthembodiment, j721: an insulating resin film 177 b is formed on tips “t”of the second pillar-shaped electrodes 16 b in the pores 15 b 3belonging to the second group so as to fill the pores 15 b 3, then,j722: an insulator layer 178 b is formed on the tips “t” of the secondpillar-shaped electrodes 16 b in the pores 15 b 3 belonging to thesecond group so as to fill the pores 15 b 3 by removing the insulatingresin film 177 b on one principal surface 14 a except the pores 15 b 3belonging to the second group. Next, f72: a first hide electrode 12 a isformed on one principal surface 14 a of the dielectric substance 14,which touches base ends “b” of the first pillar-shaped electrodes 16 a.

In the method of manufacturing the capacitor element 170 according tothe embodiment, in the same manner in the previous second embodiment,the insulator layer 178 a on the tips “t” of the first pillar-shapedelectrodes 16 a in the pores 15 a 3 belonging to the first group and theinsulator layer 178 b on the tips “t” of the second pillar-shapedelectrodes 16 b in the pores 15 b 3 belonging to the second group areformed in processes which are independent from each other in themanufacturing process.

A preferred embodiment of the insulating resin film is explained.Specifically, as materials for the insulating resin film, a polyimideresin, an epoxy resin and the like are preferable. The thickness of theinsulating resin film is preferably from several ten nm to several μm.As a forming method of the insulating resin film, well-known coatmethods such as a spin coat method, spraying method and the like can beused.

Example 7

First, the foil 13 made of Al having the length of 3.0 mm, the width of1.5 mm and the thickness of 200 μm was prepared, and the porous platedielectric substance 14 including concave portions 15 a 2 belonging tothe first group and concave portions 15 b 2 belonging to the secondgroup having different depths was formed in the same manner as theprevious Example 1.

Next, in the same manner as the Example 6, the pores 15 a 3 belonging tothe first group, the first pillar-shaped electrodes 16 a and the pores15 b 3 belonging to the second group were formed. Next, a solution ofpolyimide resin was filled so as to fill tips “t” of first pillar-shapedelectrodes 16 a in the pores 15 a 3 belonging to the first group and thepores 15 b 3 belonging to the second group of the other principalsurface 14 b side by coating the solution of polyimide resin by the spincoat method to form the insulating resin film 177 a on the otherprincipal surface 14 b of the dielectric substance 14. Next, theinsulating resin film 177 a inside the pores 15 b 3 belonging to thesecond group and on the other principal surface 14 b were removed byphotolithography, then, heat treatment was performed in an atmosphere at150° C. for 30 minutes, curing the insulating resin film 177 aselectively remaining only on the tips “t” of the first pillar-shapedelectrodes 16 a in the pores 15 a 3 belonging to the first group to formthe insulator layer 178 a made of insulating resin having the thicknessof 75 nm. Next, a second hide electrode 12 b made of Ni was formed onthe other principal surface 14 b of the dielectric substance 14 byelectroless deposition. Next, second pillar-shaped electrodes 16 b wereformed in the pores 15 b 3 belonging to the second group by Cuelectrolytic plating, using the hide electrode 12 b as a feeding powerlayer, leaving tips of the pores 15 b 3 of one principal surface 14 aside of the dielectric substance 14. Next, the insulating resin film 177b was formed on tips “t” of the second pillar-shaped electrodes 16 b inthe pores 15 b 3 belonging to the second group in the same manner asdescribed above so as to fill the pores 15 b 3 by coating the solutionof polyimide resin in the same manner as described above. Next, theinsulating resin film 177 b on one principal surface 14 a was removed byetchback, then, heat treatment was performed in the same manner asdescribed above to form the insulator layer 178 b made of the insulatingresin film having the thickness of 75 nm which fills the tips “t” of thesecond pillar-shaped electrodes 16 b in the pores 15 b 3 belonging tothe second group. Next, the first hide electrode 12 a was formed on oneprincipal surface 14 a of the dielectric substance 14 so as to touchbase ends “b” of the first pillar-shaped electrodes 16 a by Cuelectrolytic plating to obtain the capacitor element 170. In thecapacitor element 170, as in the capacitor element 10 of the Example 1,the first pillar-shaped electrode 16 a and the second pillar-shapedelectrode 16 b respectively had 30 nm in diameter, the pitch between thefirst pillar-shaped electrode 16 a and the second pillar-shapedelectrode 16 b was 70 nm, the linear dimension of a portion in which thefirst pillar-shaped electrode 16 a and the second pillar-shapedelectrode 16 b were opposed to each other was 100 μm.

Concerning the obtained capacitor element 170, electrostatic capacitywas measured by using an LCR meter 4263B manufactured by Agilent as wellas voltage proof was measured by using high-resistance meter R8340manufactured by ADVANTEST CORPORATION. As a result, the capacitor hadinitial performance in which electrostatic capacity was 0.25 mF andvoltage proof was 30V in the same manner as the Example 1.

Next, an eighth embodiment of a capacitor element included in theinvention will be explained. A capacitor element 180 according to theembodiment is different from the capacitor elements of previous first toseventh embodiments in a point that the insulator layer is made of anoxide of a second valve metal. Since the other configurations are thesame as the previous first embodiment, the explanation thereof isomitted. The capacitor element 180 of the embodiment has acharacteristic that compatibility between an insulator layer and adielectric layer is high when the insulator layer are the same materialas the dielectric layer.

Next, an eighth embodiment of a method of manufacturing the capacitorelement included in the invention will be explained with reference ofFIG. 25 to FIG. 28. FIG. 25 is a flowchart showing an outline of oneexample of manufacturing process of the method of manufacturing thecapacitor element 180 according to the embodiment. FIG. 26 and FIG. 28are longitudinal cross-sectional views corresponding to FIG. 1B forexplaining respective processes in the manufacturing process, continuedfrom FIG. 4A to FIG. 4E of the above first embodiment to FIG. 26G8 toFIG. J811, FIG. 27J812 to FIG. 27K82, and FIG. 28J821 to FIG. 28F82 inorder. Signs put to respective processes in FIG. 25 correspond to signsin parentheses of FIG. 26 to FIG. 28.

The outline of the method of manufacturing the capacitor element 180 ofthe present embodiment is as follows as shown in FIG. 25, a: a foil 13of a first valve metal is prepared, b, (d): micro concave portions 15 a1 (15 b 1) are formed on one principal surface 13 a of the foil 13 by,for example, indentation. Next, c, e: a dielectric substance 14including concave portions 15 a 2 belonging to a first group and concaveportions 15 b 2 belonging to a second group having different depths inthe one principal surface 13 a of the foil 13 is formed by, for example,anodic oxidation. Next, g8: bottom portions of the concave portions 15 a2 belonging to the first group of the dielectric substance 14 areremoved by, for example, chemical etching to form pores 15 a 3 belongingto the first group. Next, f81: a first feeding power electrode 12 a′ isformed on one principal surface 14 a of the dielectric substance 14 by,for example, electroless deposition. Next, h8: first pillar-shapedelectrodes 16 a are formed in the pores 15 a 3 belonging to the firstgroup by, for example, electrolytic plating, leaving tips of the pores15 a 3 of the other principal surface 14 b side of the dielectricsubstance 14. Next, i81: bottom portions of the concave portions 15 b 2belonging to the second group are removed by, for example, chemicaletching to form pores 15 b 3 belonging to the second group. Next, j811:a second-valve metal layer 187 a is formed on the other principalsurface 14 b of tips “t” side of the first pillar-shaped electrodes 16 ain the pores 15 a 3 belonging to the first group. Next, j812: thesecond-valve metal layer 187 a on the other principal surface 14 bexcept the inside of the pores 15 a 3 belonging to the first group isremoved. Next, j813: the second-valve metal layer 187 a is anodized toform an insulator layer 188 a made of an oxide of the second valvemetal, using the first feeding power electrode 12 a′ as a feeding powerlayer. Next, i82: the first feeding power electrode 12 a′ is removed by,for example, chemical etching. Next, k81: a second hide electrode 12 bis formed on the other principal surface 14 b of the dielectricsubstance 14, for example, by electroless deposition. Next, k82: secondpillar-shaped electrodes 16 b are formed on the second hide electrode 12b in the pores 15 b 3 belonging to the second group, leaving tips of thepores 15 b 3 of one principal surface 14 a side of the dielectricsubstance 14. Next, j821: a second-valve metal layer 187 b is formed onone principal surface 14 a of tips “t” side of the second pillar-shapedelectrodes 16 b in the pores 15 b 3 belonging to the second group. Next,j822: the second-valve metal layer 187 b on one principal surface 14 aexcept the inside the pores 15 b 3 belonging to the second group isremoved. Next, j823: the second-valve metal layer 187 b is anodized,using the second hide electrode 12 b as a feeding power layer to form aninsulator layer 188 b made of an oxide of the second valve metal. Next,f82: a first hide electrode 12 a touching base ends “b” of the firstpillar-shaped electrodes 16 a is formed on one principal surface 14 a ofthe dielectric substance 14.

In the method of manufacturing the capacitor element 180 according theembodiment, in the same manner in the previous second embodiment, theinsulator layer 188 a on the tips “t” of the first pillar-shapedelectrodes 16 a in the pores 15 a 3 belonging to the first group and theinsulator layer 188 b on the tips “t” of the second pillar-shapedelectrodes 16 b in the pores 15 b 3 belonging to the second group areformed in processes which are independent from each other in themanufacturing process.

Next, a preferred embodiment of the second valve metal is explained.Specifically, as a second valve metal, Al, Ta, Nb, Ti, Zr, Hf, Zn, W, Sband the like can be used. The thickness of the insulator layer made ofan oxide of the second valve metal is preferably several nm to severalhundred nm. Additionally, the second valve metal may the same as thefirst valve metal.

Example 8

First, the foil 13 made of Al having the length of 3.0 mm, the width of1.5 mm and the thickness of 200 μm was prepared, and the porous platedielectric substance 14 including the concave portions 15 a 2 belongingto the first group and the concave portions 15 b 2 belonging to thesecond group having different depths was formed in the same manner asthe previous Example 1.

Next, bottoms of concave portion 15 a 2 belonging to the first group wasremoved by chemical etching using an HgCl₂ solution to form the pores 15a 3 belonging to the first group. Next, the first feeding powerelectrode 12 a′ made of Ni was formed on one principal surface 14 a byelectroless deposition. Next, first pillar-shaped electrodes 16 a wereformed in the pores 15 a 3 belonging to the first group by Cuelectrolytic plating by feeding power to the first feeding powerelectrode 12 a′, leaving tips of the pores 15 a 3 of the other principalsurface 14 b side of the dielectric substance 14. Next, bottoms ofconcave portions 15 b 2 belonging to the second group were removed bychemical etching using the HgCl₂ solution to form the pores 15 b 3belonging to the second group. Next, Al was sputtered on the otherprincipal surface 14 b side of the dielectric substance 14 to form thesecond-valve metal layer 187 a made of Al on tips “t” of the firstpillar-shaped electrodes 16 a in the pores 15 a 3 belonging to the firstgroup. Next, the second-valve metal layer 187 a on the other principalsurface 14 b except the inside of the pores 15 a 3 belonging to thefirst group was removed by etchback. Next, the second-valve metal layer187 a was anodized, using the first feeding power electrode 12 a′ as afeeding power layer to form the insulator layer 188 a made of an oxideof the second valve metal (Al₂O₃) having the thickness of 3 μm. Next,the first feeding power electrode 12 a′ was removed by chemical etching.Next, the second hide electrode 12 b made of Ni was formed on the otherprincipal surface 14 b of the dielectric substance 14 by electrolessdeposition. Next, second pillar-shaped electrodes 16 b were formed inpores 15 b 3 belonging to the second group by Cu electrolytic plating,using the hide electrode 12 b as a feeding power layer, leaving tips ofthe pores 15 b 3 of one principal surface 14 a side of the dielectricsubstance 14. Next, in the same manner as described above, the insulatorlayer 188 b made of the oxide of the second valve metal (Al₂O₃) havingthe thickness of 3 μm is formed, which fills tips “t” of the secondpillar-shaped electrodes 16 b in the pores 15 b 3 belonging to thesecond group. Next, the first hide electrode 12 a was formed on oneprincipal surface 14 a of the dielectric substance 14 by Cu electrolyticplating so as to touch base ends “b” of the first pillar-shapedelectrodes 16 a to form the capacitor element 180. In the capacitorelement 180, as in the capacitor element 10 of the Example 1, the firstpillar-shaped electrode 16 a and the second pillar-shaped electrode 16 brespectively had 30 nm in diameter, the pitch between the firstpillar-shaped electrode 16 a and the second pillar-shaped electrode 16 bwas 70 nm, the linear dimension of a portion in which the firstpillar-shaped electrode 16 a and the second pillar-shaped electrode 16 bwere opposed to each other was 100 μm.

Concerning the obtained capacitor element 180, electrostatic capacitywas measured by using an LCR meter 4263B manufactured by Agilent as wellas voltage proof was measured by using high-resistance meter R8340manufactured by ADVANTEST CORPORATION. As a result, the capacitor hadinitial performance in which electrostatic capacity was 0.25 mF andvoltage proof was 30V in the same manner as the Example 1.

Next, a ninth embodiment of a capacitor element included in theinvention will be explained. A capacitor element 190 according to theembodiment is different from the capacitor elements of previous first toeighth embodiments in a point that the insulator layer is made of airspace. Since the other configurations are the same as the previous firstembodiment, the explanation thereof is omitted. The capacitor element190 of the embodiment has a characteristic that leakage current issmall.

Next, a ninth embodiment of a method of manufacturing the capacitorelement included in the invention will be explained with reference ofFIG. 29 to FIG. 31. FIG. 29 is a flowchart showing an outline of oneexample of manufacturing process of the method of manufacturing thecapacitor element 190 according to the embodiment. FIG. 30 and FIG. 31are longitudinal cross-sectional views corresponding to FIG. 1B forexplaining respective processes in the manufacturing process, continuedfrom FIG. 4A to FIG. 4E of the above first embodiment to FIG. 30G9 toFIG. 30I9, FIG. 31K91 to FIG. 31F92 in order. Signs put to respectiveprocesses in FIG. 29 correspond to signs in parentheses of FIG. 30 andFIG. 31.

The outline of the method of manufacturing the capacitor element 190 ofthe present embodiment is as follows as shown in FIG. 29, a: a foil 13of a first valve metal is prepared, b, (d): micro concave portions 15 a1 (15 b 1) are formed on one principal surface 13 a of the foil 13 by,for example, indentation. Next, c, e: a dielectric substance 14including concave portions 15 a 2 belonging to a first group and concaveportions 15 b 2 belonging to a second group having different depths inthe one principal surface 13 a of the foil 13 is formed by, for example,anodic oxidation. Next, g9: bottom portions of the concave portions 15 a2 belonging to the first group of the dielectric substance 14 areremoved by, for example, chemical etching to form pores 15 a 3 belongingto the first group. Next, f91: a first feeding power electrode 12 a′ isformed on one principal surface 14 a of the dielectric substance 14 by,for example, electroless deposition. Next, h9: first pillar-shapedelectrodes 16 a are formed in the pores 15 a 3 belonging to the firstgroup by, for example, electrolytic plating, leaving tips of the pores15 a 3 of the other principal surface 14 b side of the dielectricsubstance 14. Next, i9: a first feeding power electrode 12 a′ and bottomportions of the concave portions 15 b 2 belonging to the second groupare removed by, for example, chemical etching to form pores 15 b 3belonging to the second group. Next, k91: a second hide electrode 12 bis formed through an insulator layer 198 a made of air space betweentips “t” of the first pillar-shaped electrodes 16 a and the second hideelectrode 12 b on the other principal surface 14 b of the dielectricsubstance 14 by, for example, sputtering. Next, k92: secondpillar-shaped electrodes 16 b are formed on the second hide electrode 12b in the pores 15 b 3 belonging to the second group, leaving tips of thepores 15 b 3 of the one principal surface 14 a side of the dielectricsubstance 14. Next, f92: a first hide electrode 12 a connecting to baseends “b” of the first pillar-shaped electrodes 16 a through an insulatorlayer 198 b made of air space between the tips of the secondpillar-shaped electrodes 16 b and the first hide electrode 12 a isformed on one principal surface 14 a of the dielectric substance 14.

In the method of manufacturing the capacitor element 190 according tothe embodiment, in the same manner in the previous second embodiment,the insulator layer 198 a on the tips “t” of the first pillar-shapedelectrodes 16 a in the pores 15 a 3 belonging to the first group and theinsulator layer 198 b on the tips “t” of the second pillar-shapedelectrodes 16 b in the pores 15 b 3 belonging to the second group areformed in processes which are independent from each other in themanufacturing process.

A preferred embodiment of the air space is explained. Specifically, thethickness diameter of the air space is preferably several ten nm toseveral μm. The method of manufacturing the capacitor element 190according to the embodiment has a characteristic that the process issimple.

Example 9

First, the foil 13 made of Al having the length of 3.0 mm, the width of1.5 mm and the thickness of 200 μm was prepared, and the porous platedielectric substance 14 including concave portions 15 a 2 belonging tothe first group and concave portions 15 b 2 belonging to the secondgroup having different depths was formed in the same manner as theprevious Example 1.

Next, in the same manner as the Example 6, the pores 15 a 3 belonging tothe first group, the first pillar-shaped electrodes 16 a and the pores15 b 3 belonging to the second group were formed. Next, the second hideelectrode 12 b was formed on the other principal surface 14 b of thedielectric substance 14 by Ni-sputtering through an insulating layer 198a made of air space whose space size is 8.5 μm between the tips “t” ofthe first pillar-shaped electrodes 16 a and the second hide electrode 12b. Next, the second pillar-shaped electrodes 16 b were formed in thepores 15 b 3 belonging to the second group, using the hide electrode 12b as a feeding power layer by Cu electrolytic plating. Next, in the samemanner as described above, the first hide electrode 12 a was formed onone principal surface 14 a of the dielectric substance 14 byNi-sputtering so as to connect to base ends “b” of the firstpillar-shaped electrodes 16 a through an insulator layer 198 b made ofair space whose space size is 8.5 μm between the tips “t” of the secondpillar-shaped electrodes 16 b in the pores 15 b 3 belonging to thesecond group and the first hide electrode 12 a to obtain the capacitorelement 190. In the capacitor element 190, the first pillar-shapedelectrode 16 a and the second pillar-shaped electrode 16 b respectivelyhad 30 nm in diameter, the pitch between the first pillar-shapedelectrode 16 a and the second pillar-shaped electrode 16 b was 70 nm,the linear dimension of a portion in which the first pillar-shapedelectrode 16 a and the second pillar-shaped electrode 16 b were opposedto each other was 100 μm.

Concerning the obtained capacitor element 190, electrostatic capacitywas measured by using an LCR meter 4263B manufactured by Agilent as wellas voltage proof was measured by using high-resistance meter R8340manufactured by ADVANTEST CORPORATION. As a result, the capacitor hadinitial performance in which electrostatic capacity was 0.25 mF andvoltage proof was 30V in the same manner as the Example 1.

In all methods of manufacturing the capacitor element according to thesecond to the ninth embodiment, the insulator layer on tips of the firstpillar-shaped electrodes in pores belonging to the first group and theinsulator layer on tips of the second pillar-shaped electrodes in poresbelonging to the second group are formed in processes which areindependent from each other in the manufacturing process as describedabove.

Accordingly, the invention is not limited to the above respectiveembodiments, and for example, the insulator layer on the tips of thefirst pillar-shaped electrodes and the insulator layer on tips of thesecond pillar-shaped electrodes are formed by insulator layers ofmaterials different from each other. Also, when the length of the firstpillar-shaped electrodes and the length of the second pillar-shapedelectrodes are different, for example, insulator layers havingthicknesses different from each other can be formed.

Next, a first embodiment of a capacitor using the capacitor elementincluded in the invention will be explained with reference to FIG. 32.FIG. 32 shows a capacitor 20 including the capacitor element 10 of thefirst embodiment as a capacitor unit CU. In the capacitor 20, terminalportions 29 a, 29 b respectively made of, for example, a conductivemetallic plate are connected to the first hide electrode 12 a and thesecond hide electrode 12 b as well as an exterior resin covering thecapacitor unit CU is included.

It is preferable to apply Cu, phosphorous bronze, various types ofstainless steels, Ni42-Fe alloy and the like as the terminal portions 29a, 29 b. The connection between the hide electrodes 12 a, 12 b and theterminal portions 29 a, 29 b are preferably performed byresistance-welding, diffused junction, adhesion by conductive adhesivessuch as a carbon paste and the like, though not shown.

Next, a second embodiment of a capacitor using the capacitor elementincluded in the invention will be explained with reference to FIG. 33.FIG. 33 shows a capacitor 30 including the capacitor elements 10 of thefirst embodiment as capacitor units CU1, CU2 and CU3. Respectivecapacitor units CU1, CU2 and CU3 are connected in parallel with terminalportions 39 a, 39 b, respectively, which have large electrostaticcapacity.

Next, an embodiment of a capacitor-embedded multilayer interconnectionsubstrate using the capacitor element included in the invention will beexplained with reference to FIG. 34. FIG. 34 shows a capacitor-embeddedmultilayer interconnection substrate 40 including the capacitor element10 of the first embodiment as a capacitor unit.

In the capacitor-embedded multilayer interconnection substrate 40, thecapacitor unit CU is embedded at the bottom thereof, in which the firsthide electrode 12 a is connected to an internal conductor of thecapacitor-embedded multilayer interconnection substrate 40.Additionally, the second hide electrode 12 b is exposed at the bottom ofthe multilayer interconnection substrate with other terminal electrodes.

The invention is suitable to be applied to various electronic deviceswhich are light, thin, short and small, using a small-sized andlarge-capacity capacitor.

The present application claims priority to Japanese Patent ApplicationNo. 2007-197039, filed Jul. 30, 2007, and No. 2007-329326, filed Dec.12, 2007, the disclosure of which is incorporated herein by reference inits entirety.

It will be understood by those of skill in the art that numerous andvarious modifications can be made without departing from the spirit ofthe present invention. Therefore, it should be clearly understood thatthe forms of the present invention are illustrative only and are notintended to limit the scope of the present invention.

1. A method of manufacturing a capacitor element, comprising: formingmicro concave portions at plural positions on one principal surface of afoil of a first valve metal by indentation; forming a porous platedielectric substance by performing anodic oxidation to the foil of thevalve metal and by forming, on one principal surface side of thedielectric substance, concave portions belonging to a first group havinga determinable depth at positions in which the micro concave portionsare formed and by forming, on the one principal surface side of thedielectric substance, concave portions belonging to a second grouphaving a depth shallower than the concave portions belonging to thefirst group at positions between the plural positions in which the microconcave portions are formed by performing anodic oxdidation; forming aseed layer at inner surfaces of the concave portions belonging to thefirst group of the dielectric substance and at inner surfaces of theconcave portions belonging to the second group by electroless depositionas well as forming a first hide electrode on the one principal surfaceof the dielectric substance; forming plural pores belonging to a firstgroup opening at another principal surface side of the dielectricsubstance by removing bottom portions of the concave portions belongingto the first group of the dielectric substance by etching; forming firstpillar-shaped electrodes on the seed layer in the pores belonging to thefirst group by electrolytic plating, leaving tips of the pores of theanother principal surface side of the dielectric substance; formingplural pores belonging a second group opening at the another principalsurface side of the dielectric substance by removing bottom portions ofthe concave portions belonging to the second group in the dielectricsubstance by etching; forming electroconductive polymer layers on thetips of the first pillar-shaped electrodes in the pores belonging to thefirst group and on the first hide electrode in the pores belonging tothe second group so as to fill the pores respectively byelectropolymerization; forming second pillar-shaped electrodes on theseed layer at inner surfaces of the pores belonging to the second groupby electrolytic plating as well as forming a second hide electrode onthe another principal surface of the dielectric substance; forming aninsulator layer by pyrolyizing each electroconductive polymer layer tobe insulated; and burning off short-circuit points between the tips ofthe first pillar-shaped electrodes and the second hide electrode andbetween the tips of the second pillar-shaped electrodes and the firsthide electrodes by applying voltage.
 2. A method of manufacturing acapacitor element, comprising: forming micro concave portions at pluralpositions on one principal surface of a foil of a first valve metal byindentation; forming a porous plate dielectric substance by performinganodic oxidation to the foil of the valve metal and by forming, on oneprincipal surface side of the dielectric substance, concave portionsbelonging to a first group having a determinable depth at positions inwhich the micro concave portions are formed and by forming, on the oneprincipal surface side of the dielectric substance, concave portionsbelonging to a second group having a depth shallower than the concaveportions belonging to the first group at positions between the pluralpositions in which the micro concave portions are formed; forming pluralpores belonging to a first group opening at another principal surfaceside of the dielectric substance by removing bottom portions of concaveportions belonging to the first group of the dielectric substance byetching; forming a first feeding power electrode on the one principalsurface on which concave portions belonging to the second group of thedielectric substance are formed; forming first pillar-shaped electrodesin the pores belonging to the first group by electrolytic plating,leaving tips of the pores of the another principal surface side of thedielectric substance; forming an insulator layer on the tips of thefirst pillar-shaped electrodes in the pores belonging to the first groupso as to fill the pores respectively; forming plural pores belonging toa second group opening at the another principal surface side of thedielectric substance by removing the first feeding power electrode onthe one principal surface of the dielectric substance and bottomportions of the concave portions belonging to the second group byetching; forming a second hide electrode on the another principalsurface of the dielectric substance; forming second pillar-shapedelectrodes on the second hide electrode in the pores belonging to thesecond group by electrolytic plating, leaving tips of the pores of theone principal surface side of the dielectric substance; forming aninsulator layer on the tips of the second pillar-shaped electrodes inthe pores belonging to the second group so as to fill the pores; andforming a first hide electrode on the one principal surface of thedielectric substance so as to touch base ends of the first pillar-shapedelectrodes.
 3. The method of manufacturing the capacitor elementaccording to claim 2, wherein, in the step of forming the insulatorlayer on the tips of the first pillar-shaped electrodes and the step offorming the insulator layer on the tips of the second pillar-shapedelectrodes, electroconductive polymer films are formed by using thefirst feeding power electrode and the second feeding power electrode asfeeding power layers respectively, and then the films are insulated bypyrolysis.
 4. The method of manufacturing the capacitor elementaccording to claim 2, wherein, in the step of forming the insulatorlayer on the tips of the first pillar-shaped electrodes and the step offorming the insulator layer on the tips of the second pillar-shapedelectrodes, TiO₂ electrodeposited films are formed by using the firstfeeding power electrode and the second hide electrode as feeding powerelectrodes respectively, and then the films are insulated by performingheat treatment.
 5. The method of manufacturing the capacitor elementaccording to claim 2, wherein, in the step of forming the insulatorlayer on the tips of the first pillar-shaped electrodes and the step offorming the insulator layer on the tips of the second pillar-shapedelectrodes, SiO₂ layers are formed by electrolytic plating by using thefirst feeding power electrode and the second hide electrode as feedingpower layers respectively.
 6. The method of manufacturing the capacitorelement according to claim 2, wherein, in the step of forming theinsulator layer on the tips of the first pillar-shaped electrodes andthe step of forming the insulator layer on the tips of the secondpillar-shaped electrodes, Sn—Pd plating layers are formed by using thefirst feeding power electrode and the second hide electrode as feedingpower layers respectively, and then SiO₂ layers are wet-accumulated onthe Sn—Pd plating layers.
 7. A method of manufacturing a capacitorelement, comprising: forming micro concave portions at plural positionsin a predetermined arrangement on one principal surface of a foil of afirst valve metal by indentation; forming a porous plate dielectricsubstance by performing anodic oxidation to the foil of the valve metaland by forming, on one principal surface side of the dielectricsubstance, concave portions belonging to a first group having adeterminable depth at positions in which the micro concave portions areformed and by forming, on the one principal surface side of thedielectric substance, concave portions belonging to a second grouphaving a depth shallower than the concave portions belonging to thefirst group at positions between the plural positions in which the microconcave portions are formed; forming plural pores belonging to a firstgroup opening at another principal surface side of the dielectricsubstance by removing bottom portions of the concave portions belongingto the first group of the dielectric substance by etching; forming afirst feeding power electrode on the one principal surface on which theconcave portions belonging to the second group of the dielectricsubstance are formed; forming first pillar-shaped electrodes on thefeeding power electrode in pores belonging to the first group byelectrolytic plating, leaving tips of the pores of the another principalsurface side of the dielectric substance; forming plural pores belongingto a second group opening at the another principal surface side of thedielectric substance by removing the first feeding power electrode andbottom portions of the concave portions belonging to the second group ofthe dielectric substance by etching; forming an insulator layer on thetips of the first pillar-shaped electrodes in the pores belonging to thefirst group so as to fill the pores respectively; forming a second hideelectrode on the another principal surface of the dielectric substance;forming second pillar-shaped electrodes on the second hide electrode inthe pores belonging to the second group by electrolytic plating, leavingtips of the pores of the one principal surface side of the dielectricsubstance; forming an insulator layer on the tips of the secondpillar-shaped electrodes in the pores belonging to the second group soas to fill the pores respectively; and forming a first hide electrode onthe one principal surface of the dielectric substance so as to touchbase ends of the first pillar-shaped electrodes.
 8. The method ofmanufacturing the capacitor element according to claim 7, wherein, inthe step of forming the insulator layer on the tips of the firstelectrodes, an insulating resin is buried on tips of the firstpillar-shaped electrodes in the pores belonging to the first group andthe pores belonging to the second group respectively, and then theinsulating resin in the pores belonging to the second group is removed;and wherein, in the step of forming the insulator layer on the tips ofthe second pillar-shaped electrodes, an insulating resin is buried ontips of the second pillar-shaped electrodes of the pores belonging tothe second group respectively.
 9. The method of manufacturing thecapacitor element according to claim 7, wherein, in the step of formingthe insulator layer on the tips of the first pillar-shaped electrodes,an insulating resin film is formed on the other principal surface of thetips side of the first pillar-shaped electrodes of the dielectricsubstance, and then the insulating resin film on the another principalsurface except the inside of pores belonging to the first group isremoved; and wherein, in the step of forming the insulator layer on thetips of the second pillar-shaped electrodes, an insulating resin film isformed on the one principal surface of tips side of the secondpillar-shaped electrodes of the dielectric substance, and then theinsulating resin film on the one principal surface except the inside ofthe pores belonging to the second group is removed.
 10. A method ofmanufacturing a capacitor element, comprising: forming micro concaveportions at plural positions on one principal surface of a foil of afirst valve metal by indentation; forming a porous plate dielectricsubstance by performing anodic oxidation to the foil of the valve metaland by forming, on one principal surface side of the dielectricsubstance, concave portions belonging to a first group having adeterminable depth at positions in which the micro concave portions areformed and by forming, on the one principal surface side of thedielectric substance, concave portions belonging to a second grouphaving a depth shallower than the concave portions belonging to thefirst group at positions between the plural positions in which the microconcave portions are formed; forming plural pores belonging to a firstgroup opening at another principal surface side of the dielectricsubstance by removing bottom portions of the concave portions belongingto the first group of the dielectric substance by etching; forming afirst feeding power electrode on the one principal surface on which theconcave portions belonging to the second group of the dielectricsubstance are formed; forming first pillar-shaped electrodes on thefeeding power electrode in the pores belonging to the first group byelectrolytic plating, leaving tips of the pores of the another principalsurface side of the dielectric substance; forming plural pores belongingto a second group opening at the another principal surface side of thedielectric substance by removing bottom portions of the concave portionsbelonging to the second group of the dielectric substance by etching;forming a second-valve metal layer on the another principal surface ofthe tips side of the first pillar-shaped electrodes of the dielectricsubstance; removing the second-valve metal layer on the anotherprincipal surface except the inside of pores belonging to the firstgroup; forming an insulator layer on the tips of the first pillar-shapedelectrode in the pores belonging to the first group as well as into theplural pores belonging to the second groups by performing anodicoxidation to the second-valve metal layer using the first feeding powerelectrode as a feeding power layer so as to fill the pores respectively;removing the first feeding power electrode by etching; forming a secondhide electrode on the another principal surface of the dielectricsubstance; forming second pillar-shaped electrodes on the second hideelectrode in the pores belonging the second group by electrolyticplating, leaving tips of the pores of the one principal surface side ofthe dielectric substance; forming a second-valve metal layer on the oneprincipal surface of the tips side of the second pillar-shapedelectrodes of the dielectric substance; removing the second-valve metallayer on the one principal surface except the inside of the poresbelonging to the second group; forming an insulator layer on the tips ofthe second pillar-shaped electrodes in the pores belonging to the secondgroup so as to fill the pores respectively; and forming a first hideelectrode on the one principal surface of the dielectric substance so asto touch based ends of the first pillar-shaped electrodes by performinganodic oxidation to the second-valve metal layer by using the secondhide electrode as a feeding power layer.
 11. A method of manufacturing acapacitor element, comprising: forming micro concave portions at pluralpositions on one principal surface of a foil of a first valve metal byindentation; forming a porous plate dielectric substance by performinganodic oxidation to the foil of the valve metal and by forming, on oneprincipal surface side of the dielectric substance, concave portionsbelonging to a first group having a determinable depth at positions inwhich the micro concave portions are formed and by forming, on the oneprincipal surface side of the dielectric substance, concave portionsbelonging to a second group having a depth shallower than the concaveportions belonging to the first group at positions between the pluralpositions in which the micro concave portions are formed; forming pluralpores belonging to a first group opening at another principal surfaceside of the dielectric substance by removing bottom portions of theconcave portions belonging to the first group of the dielectricsubstance by etching; forming a first feeding power electrode on the oneprincipal surface on which the concave portions belonging to the secondgroup of the dielectric substance are formed; forming firstpillar-shaped electrodes on the feeding power electrode in the poresbelonging to the first group by electrolytic plating, leaving tips ofthe pores of the another principal surface side of the dielectricsubstance; forming plural pores belonging to a second group opening atthe another principal surface side of the dielectric substance byremoving the first feeding power electrode and bottom portions of theconcave portions belonging to the second group of the dielectricsubstance by etching; forming a second hide electrode on the anotherprincipal surface of the dielectric substance by sputtering through airspace between the tips of the first pillar-shaped electrodes and thesecond hide electrode; forming second pillar-shaped electrodes on thesecond hide electrode in the pores belonging to the second group byelectrolytic plating, leaving tips of one principal surface side of thedielectric substance; and forming a first hide electrode connecting tobase ends of the first pillar-shaped electrodes on the one principalsurface of the dielectric substance by sputtering through air spacebetween the tips of the second pillar-shaped electrodes and the firsthide electrode.